The Montgomery Guards were an Irish-American militia company that formed in Boston in 1837 and were forced to disband the following year due to extreme nativist and anti-Catholic sentiment in the city.
On September 12, 1837, at the annual fall muster on Boston Common, six companies of militiamen marched off the field to protest the inclusion of the Montgomery Guards. Afterwards, as the company's forty members marched down Tremont Street to their armory, they were mobbed by about 3,000 angry spectators who pelted them with bottles and rocks and threatened to storm the building.
City officials and the press strongly denounced the riot and praised the Montgomery Guards for their restraint. Nevertheless, Governor Edward Everett ordered the disbandment of the company for public safety reasons. Another company by the same name was formed sometime after the American Civil War.