Colonel Alexander Smith served in the Morgan Volunteers, a Baltimore-based company of the organized militia of the state of Maryland during the 1830s (the organized militia being the ancestor of the modern day Army National Guard). The Morgan Volunteers were a specialized unit, armed with rifles supplied by the state armorer at Annapolis.  
This portrait and its companion piece (Walters 37.2774) are among Miller's few early documented works. The colonel's account book lists a payment of seventy-five dollars made for this pair of portraits on April 1, 1833.
<bdi><a href="https://en.wikipedia.org/wiki/en:Alfred_Jacob_Miller" class="extiw" title="w:en:Alfred Jacob Miller"><span title="American painter (1810-1874)">Alfred Jacob Miller</span></a>
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1833<div style="display: none;">date QS:P571,+1833-00-00T00:00:00Z/9</div>
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