At the peak of his long congressional career, Kirwan was hailed as one of the most influential Democratic members of Congress, particularly on matters related to conservation.

[2] In 1907, he relocated to Youngstown, Ohio, a center of steel production located just west of the Pennsylvania border.

During the First World War Kirwan served overseas as a sergeant in the Three Hundred and Forty-eighth Machine Gun Company with the Sixty-fourth Artillery, United States Army.

[3] Despite his later occupancy of important committee positions, however, Kirwan was unsuccessful in his efforts to achieve his most cherished goal as a lawmaker.

Upon its completion, Kirwan lauded the housing project as a welcome alternative to what had been a dilapidated residential district, and further declared that it would serve as a model for the nation.

[8] Among the highlights of Kirwan's later career was an event held in his honor at Youngstown's Idora Park Ballroom.

[2] While aspects of Kirwan's legacy have proved durable, the constituency he served was adversely affected by deindustrialization, which swept through much of northeastern Ohio starting in the late 1970s.

The Michael J. Kirwan Reservoir impounds the west branch of the Mahoning River in Portage County, Ohio.