For the rest of his life, Underwood was devoted to genealogy and the
Lost Cause of the Confederacy through the
United Confederate Veterans. He raised money to construct a Confederate Memorial at
Oak Woods Cemetery in
Chicago, Illinois to commemorate the Confederate prisoners who died at Camp Douglas, and whose remains were exhumed and moved there after closure of the previous cemetery and expansion of
Grant Park during urban renewal following the
Great Chicago Fire of 1871. Underwood then agreed to raise money for a Confederate monument in
Richmond, Virginia. However, the project was embroiled in legal controversies which ruined him financially and physically. In 1910, oil portraits of many of the twenty Confederate generals he had commissioned from
E.F. Andrews were auctioned by a
Covington, Kentucky warehouse to pay storage fees, and most ended up in Virginia. Underwood died on October 29, 1913, in
Manhattan,
New York. His remains were returned to Kentucky for burial in the family plot at Fairview cemetery in Bowling Green. ==Legacy==