Constans I | Byzantine, Reformer, Conqueror

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<div class="drawer d-flex flex-column open"> <div class="left-rail-section-content"> <div class="topic-left-rail-header text-truncate bg-gray-50 position-relative text-right d-flex align-items-center"> <div class="tlr-title px-20 py-15 text-left"> <em class="material-icons text-gray-400 d-lg-none" data-icon="toc"></em> <a class="font-serif font-weight-bold text-black link-blue" href="https://www.britannica.com/biography/Constans-I">Constans I</a> </div> <button aria-label="Close" class="js-sections-close-button btn-link btn-sm btn d-lg-none position-absolute top-0 p-10 right-0" > <em class="material-icons font-26" data-icon="close"></em> </button> </div> <div class="section-content pl-10 pr-20 pl-sm-50 pr-sm-60 pl-lg-5 pr-lg-10 pt-10 pt-lg-0 bg-gray-50 clear-catfish-ad"> <div class="toc mb-20"> <div class="font-serif font-14 font-weight-bold mx-15 mb-15 mt-20"> Table of Contents </div> <span class="toc-extra-link selected link-gray-900 mt-15"> Introduction </span> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/biography/Constans-I/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900" href="/facts/Constans-I">Quick Facts & Related Topics</a> </div> <div class="mb-30 tlr-related-quizzes"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Quizzes </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/quiz/kings-and-emperors-part-iii-quiz"> <img loading="lazy" src="https://cdn.britannica.com/95/115195-131-5A6187D9/Napoleon-His-Imperial-Robes-Francois-Gerard-Versailles-1805.jpg?w=200&h=200&c=crop" alt="Napoleon Bonaparte. Napoleon in Coronation Robes or Napoleon I Emperor of France, 1804 by Baron Francois Gerard or Baron Francois-Pascal-Simon Gerard, from the Musee National, Chateau de Versailles." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/quiz/kings-and-emperors-part-iii-quiz" >Kings and Emperors (Part III) Quiz</a> </div> </div> </div> <div class="mb-30 tlr-discover"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Discover </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/7-female-firsts-in-us-politics"> <img loading="lazy" src="https://cdn.britannica.com/91/61891-131-AF35D0B4/Frances-Perkins.jpg?w=200&h=200&c=crop" alt="Frances Perkins, c. 1939-1945" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/7-female-firsts-in-us-politics" >7 Female Firsts in U.S. Politics</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/10-greatest-baseball-players-of-all-time"> <img loading="lazy" src="https://cdn.britannica.com/35/146135-131-BC5E7D00/Baseball-grass-arts-Homepage-blog-entertainment-sports-2010.jpg?w=200&h=200&c=crop" alt="Baseball laying in the grass. Homepage blog 2010, arts and entertainment, history and society, sports and games athletics" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-greatest-baseball-players-of-all-time" >10 Greatest Baseball Players of All Time</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/plato-and-aristotle-how-do-they-differ"> <img loading="lazy" src="https://cdn.britannica.com/75/177675-131-B7B445EB/detail-Aristotle-School-of-Athens-Plato-Raphael.jpg?w=200&h=200&c=crop" alt="Plato (left) and Aristotle, detail from School of Athens, fresco by Raphael, 1508-11; in the Stanza della Segnatura, the Vatican. Plato points to the heavens and the realm of Forms, Aristotle to the earth and the realm of things." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/plato-and-aristotle-how-do-they-differ" >Plato and Aristotle: How Do They Differ?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/14-tough-questions-answered"> <img loading="lazy" src="https://cdn.britannica.com/91/219491-131-8BCF8E53/human-Inuit-skull.jpg?w=200&h=200&c=crop" alt="A human Inuit skull in a stone chambered cairn in Ilulissat in Greenland. 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class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/why-is-the-mona-lisa-so-famous"> <img loading="lazy" src="https://cdn.britannica.com/24/189624-131-BAF1184D/Mona-Lisa-oil-wood-panel-Leonardo-da.jpg?w=200&h=200&c=crop" alt="Mona Lisa, oil on wood panel by Leonardo da Vinci, c. 1503-06; in the Louvre, Paris, France. 77 x 53 cm." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/why-is-the-mona-lisa-so-famous" >Why Is the <em>Mona Lisa</em> So Famous?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" 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They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> The Editors of Encyclopaedia Britannica</span></div> <div class="last-updated font-12 font-serif"> <a class="byline-edit-history" href="https://www.britannica.com/biography/Constans-I/additional-info#history" rel="nofollow">Article History</a> </div></div> </div> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button d-none d-sm-block js-sections-inline-button module-spacing btn d-lg-none"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <div class="d-flex d-sm-none flex-row"> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button js-sections-inline-button module-spacing"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <button class="ai-ask-button btn border-2 ai-ask-button btn border-2 module-spacing btn-sm js-inline-ai-ask-button btn-outline-red-400 border-red-400 p-10 ml-5"> Ask the Chatbot a Question </button> </div> <div class="js-qf-module qf-module px-40 px-sm-20 py-15 mx-auto module-spacing font-14 bg-gray-50 rounded"> <div class="qf-title font-weight-bold font-14 mb-10 text-center"> Quick Facts</div> <div class="facts-list mt-10"> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Original name: </dt> <dd>Flavius Julius Constans</dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Born: </dt> <dd>c. 323</dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Died: </dt> <dd>350, <a href="/place/Gaul-ancient-region-Europe">Gaul</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Also Known As: </dt> <dd>Flavius Julius Constans</dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Title / Office: </dt> <dd><a href="/topic/emperor-title">emperor (337-350)</a>, <a href="/place/Roman-Empire">Roman Empire</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> <div class="text-center"> <a class="btn btn-sm btn-link p-0" href="/facts/Constans-I"> See all related content </a> </div> </div> </div> </div><span class="marker before-article"></span><section data-level="1" id="ref1"><span class="marker PREMOD1 mod-inline"></span><p class="topic-paragraph"><strong><span id="ref71515"></span>Constans I</strong> (born c. 323—died 350, Gaul) was a Roman <a href="https://www.britannica.com/topic/emperor-title" class="md-crosslink autoxref " data-show-preview="true">emperor</a> from 337 to 350.</p><span class="marker MOD1 mod-inline"></span><span class="marker PREMOD2 mod-inline"></span><p class="topic-paragraph">The youngest son of <span id="ref749611"></span><a href="https://www.britannica.com/biography/Constantine-I-Roman-emperor" class="md-crosslink " data-show-preview="true">Constantine the Great</a> (reigned 306–337), Constans was proclaimed caesar by his father on December 25, 333. When <a href="https://www.britannica.com/biography/Constantine-Roman-emperor" class="md-crosslink autoxref " data-show-preview="true">Constantine</a> died on September 9, 337, Constans and his two brothers, <a href="https://www.britannica.com/biography/Constantius-II" class="md-crosslink " data-show-preview="true">Constantius II</a> and <span id="ref71516"></span><a href="https://www.britannica.com/biography/Constantine-II-antipope" class="md-crosslink " data-show-preview="true">Constantine II</a>, each adopted the title of <a href="https://www.britannica.com/biography/Augustus-Roman-emperor" class="md-crosslink autoxref " data-show-preview="true">Augustus</a> and divided the empire among themselves. Constans took control of <a href="https://www.britannica.com/place/Italy" class="md-crosslink autoxref " data-show-preview="true">Italy</a>, Africa, and Illyricum (in the northwestern Balkans). In 340 Constantine II—ruler of Spain, <a href="https://www.britannica.com/place/Gaul-ancient-region-Europe" class="md-crosslink autoxref " data-show-preview="true">Gaul</a>, and Britain—invaded northern Italy but was defeated and killed by Constans’s army at <a href="https://www.britannica.com/place/Aquileia" class="md-crosslink autoxref " data-show-preview="true">Aquileia</a>. This victory gave Constans, who at the time of the battle was at Naissus (modern Niš, Yugoslavia), control over the entire western half of the empire. He defended his realm successfully against the Franks in 341 and two years later visited Britain (he was the last <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="legitimate" href="https://www.merriam-webster.com/dictionary/legitimate" data-type="MW">legitimate</a> emperor to visit). In 350 he was overthrown and killed at Autun in Gaul by the usurper <a href="https://www.britannica.com/biography/Magnentius" class="md-crosslink " data-show-preview="true">Magnus Magnentius</a>.</p><div class="one-good-fact-module"> </div><span class="marker MOD2 mod-inline"></span><span class="marker PREMOD3 mod-inline"></span><p class="topic-paragraph">An <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="ardent" href="https://www.merriam-webster.com/dictionary/ardent" data-type="MW">ardent</a> orthodox Christian, Constans was known as a vigorous opponent of <a href="https://www.britannica.com/topic/Arianism" class="md-crosslink autoxref " data-show-preview="true">Arianism</a> (a doctrine that affirmed the created, finite nature of Christ) and paganism and a supporter of Athanasius of Alexandria, the great defender of Trinitarian Christianity.</p><a class="link-module shadow-sm d-block qa-quiz-module" href="/quiz/kings-and-emperors-part-iii-quiz" data-link-module-iframe-link=""> <img loading="lazy" src="https://cdn.britannica.com/95/115195-131-5A6187D9/Napoleon-His-Imperial-Robes-Francois-Gerard-Versailles-1805.jpg" alt="Napoleon Bonaparte. Napoleon in Coronation Robes or Napoleon I Emperor of France, 1804 by Baron Francois Gerard or Baron Francois-Pascal-Simon Gerard, from the Musee National, Chateau de Versailles." class="rounded-sm mr-15" width="70" /> <div class="line-clamp clamp-5"> <div class="module-title bg-green">Britannica Quiz</div> <div class="font-weight-semi-bold mt-5">Kings and Emperors (Part III) Quiz</div> </div> </a><span class="marker MOD3 mod-inline"></span></section> <span class="md-signature">This article was most recently revised and updated by <a href="/contributor/encyclopaedia-britannica/12989892">Encyclopaedia Britannica</a>.</span><span class="marker end-of-content"></span><span class="marker after-article"></span></div> <div id="chatbot-root"></div> </div> </div> </div> <div class="ai-dialog-placeholder"></div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div> </article></div> </div></div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"DESKTOP","pageNumber":1,"pagesTotal":1,"pageId":133741,"pageLength":196,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-130/js/libs/jquery-3.5.0.min.js?v=3.130.14"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-130/dist/topic-page.js?v=3.130.14' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"B","adLeg":"B","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"BIO_SMALL","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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Constans I | Byzantine, Reformer, Conqueror | Britannica