[2] After attending Oberlin College for seven months, Lennon moved to Denver, Colorado, where he worked first as a farmer and miner before returning to the tailor's trade.

In 1894, when Gompers lost the AFL presidency for a year to socialist labor leader John McBride, he worked out of Lennon's New York City office.

[2] Both Lennon and Gompers held the conservative AFL labor philosophy of "pure and simple unionism" against socialist and anarchist viewpoints that put forward a larger political project of working-class emancipation through the overthrow of capitalism.

In 1894, the Journeyman Tailors Union under Lennon's leadership faced a blow when it lost half its members due to a disastrous strike in New York.

[2] He would spend the rest of his life in Bloomington, where he was also known for his religious advocacy in the Presbyterian and Unitarian Churches and for the cause of alcohol prohibition through his involvement in the Anti-Saloon League.

[1][2][4] In 1919, Lennon supported the formation of the Illinois Labor Party, although AFL president Samuel Gompers, his friend and close confidant, opposed the effort.