Why is "3rd Battalion Massachusetts Rifles" trending?

Wikipedia Overview

The 3rd Battalion Massachusetts Rifles was an infantry unit created at the start of the American Civil War and activated for federal service in the Union army for a term of ninety days. It consisted of three companies of prewar militia and one newly recruited company together organized under the command of Major Charles Devens. The term "rifles" was a designation frequently given to antebellum militia companies which trained in the use of rifled muskets—a relatively new innovation at the time—as opposed to smoothbore muskets. Only minor differences in training and tactics differentiated such units from a typical infantry company of the time. During the 1840s, "rifle" companies were often expected to train and serve as skirmishers in open order, however by the Civil War, United States army tactics manuals made no distinction between a company of "rifles" and a typical infantry company.