Donald Williams, author of Shamrocks and Pluff Mud, sent along this bit from the May 7, 1861 edition of the Charleston Mercury, explaining the actions of the Charleston Meagher Guards militia regarding the individual in whose honor they took their name (see here):
At a meeting of the Meagher Guards, held at the Military Hall on the evening of the 6th inst., the following preamble and resolutions were unanimously adopted:
The report of the committee appointed to inquire into the truth of the rumor that THOMAS FRANCIS MEAGER, Esq. (in honor of whose patriotic efforts for the liberation of Ireland this company was named) had joined the crusade against the Southern States, having been heard—
1. Resolved, That the same be confirmed.
And, whereas, from the said Report, it appears to be true that Mr. Meagher has been carried away by the fanaticism of the North, and has enrolled himself in the ranks of our enemies, taking arms against us in this most unholy war, in support of usurpation and oppression, thus proving himself recreant to the sacred principles of liberty, of which he was hitherto an uncompromising an advocate; therefore,
2. Resolved, That, remembering the services of Mr. MEAGHER in the cause of freedom in Ireland, this Company have learned with infinite disappointment and regret that he too, should have joined the oppressors of this their adopted land.
3. Resolved, That under these circumstances this company can no longer, consistently with its position and dignity, bear his name, and that the same be and hereby is repudiated by them.
4. Resolved, That the name of THOMAS FRANCIS MEAGHER be erased from the roll of the honorary members of this Company.
5. Resolved, That it be referred to a Committee to suggest some suitable name by which this Company shall hereafter be known.
6. Resolved, That a copy of these preamble and resolutions be published in the daily papers of this city, and in the New York, Day Book