Politically active throughout much of his adult life, he was a contributor to the Underground Railroad and also helped to secure the post-war passage of key civil rights legislation in Pennsylvania.

[6] A member of the prominent Bustill family, he was a cousin and student of artist Robert Douglass Jr., who trained at the Pennsylvania Academy of Fine Arts and was a pupil of Thomas Sully.

Respected for their civic engagement and philanthropy, David B. and Elizabeth Bowser supported their family by designing and painting banners, signs, uniform hats and other regalia for fraternal associations, political groups, and volunteer fire companies in and beyond Philadelphia.

Active in that decade's efforts to repeal the clause in Pennsylvania's Constitution which prohibited blacks from voting, Bowser and his family also became so involved with the abolition movement that their home became a stop on the Underground Railroad.

"[11] Bowser's work on the first banner was paid for through a commission awarded by the Contraband Relief Association (CRA), an organization headed by Elizabeth Keckley, the formerly enslaved woman who became Mary Todd Lincoln's dressmaker.

[15] With respect to the other Bowser-designed battle flags, historians at the Pennsylvania Historical and Museum Commission note that:[8] The 127th and 3rd regiments marched carrying banners reading 'We will prove ourselves men' and 'Rather Die Freemen, Than Live To Be Slaves.'

'For the 22nd USCT banner, Bowser depicted a black soldier pointing "a bayonet at the chest of a Confederate who has allowed his flag to fall and who is tossing aside his sword," beneath the words, "Sic semper tyrannis" ("thus always to tyrants"), a phrase which would come to have an entirely different meaning two years later when shouted by John Wilkes Booth after his assassination of Lincoln at Ford's Theater.

The June 24 event, which began at 8 p.m. at Franklin Hall on Sixth Street below Arch, was held to increase support for the Union Army's recruitment of black soldiers.

Frederick Douglass also rose to speak, and also gave a lengthy address in which he reflected on his life during and after his enslavement and stressed the urgent need for black men to fill up new regiments "for the purpose of upholding the stars and stripes, and crushing out the rebellion of the slaveholders."

James A. Jones, who "opened the proceedings with prayer"; Robert Purvis, who delivered an address; Jacob C. White, Jr., who "read the proclamation of the ratification of the fifteenth amendment"; and the Hon.

Afterward, the group approved a resolution which "recognize[d] the Anti-Slavery Society, the Republican party and press, the Equal Rights League, John Brown, Abraham Lincoln, Ulysses S. Grant, Charles Sumner, William Lloyd Garrison, Horace Greeley, Lucretia Mott, and the whole army of pioneers who spoke or ventured heroic deeds in behalf of their oppressed people, as among the human agencies that crystallized into law the Declaration for which our fathers died; that they regarded the restoration of this privilege as a vindication of popular government, and that therein was recognized their just claims to all the franchises granted to any other class of their fellow-citizens; that in the future, as in the past, they will be found on the side of loyalty and patriotism [with] an unfaltering adherence to the Republican party.

"[22] As vice president of the Pennsylvania Equal Rights League, Bowser was also among those who motivated the organization's membership to meet with President Grant at the White House on November 26, 1872 "for the purpose ... of urging upon him the importance of recommending in his annual message to Congress, a request kindred to the 'Fifteenth Amendment,' by the recommendation of the passage of such laws as will require that all the citizens of this country shall be protected from insult and outrage on the highways of the nation, and secured in all their 'public rights' — that all may have the full benefit of the unfaltering loyalty which, at the fearful price of life and suffering, we gave to our country; the full benefit of our taxes which we fully, freely and uncomplainingly pay; that ... Congress [will] pass such laws as will protect us in the attempt to exercise and enjoy our civil rights."