A battle flag that flew alongside a Pennsylvania regiment of black troops in the Civil War will be auctioned in Denver on Thursday.

The artifact, which represents the 127th Regiment of the U.S. Colored Troops, is being sold by the Grand Army of the Republic Museum in Philadelphia to bolster the museum’s finances, according to Anthony Waskie, its vice president.

The silk flag was painted by David Bustill Bowser, a prominent black artist of the 19th century commissioned by the Union League of Philadelphia to create flags for the state’s USCT regiments, Waskie said. It depicts a black soldier waving to Columbia, the Goddess of Liberty with the inscription “We will prove ourselves men.”

The other flags are thought to have been destroyed at West Point in the 1940s, which Waskie believes makes the 127th Regiment flag the last remaining USCT flag in existence, he said.

The minimum bid for the flag is $75,000, according to Morphy Auctions’ website.

The 1,000 men from the 127th Regiment were recruited from Pennsylvania, New Jersey and Delaware and trained at Camp William Penn in Cheltenham before being mustered into service in late 1864, Waskie said. Soldiers from the regiment served in limited combat and some were present at Robert Lee’s surrender at Appomattox (Virginia) the following year.

Records indicate that some black troops from Pennsylvania, mostly farm laborers, lived and worked in Lancaster County before and after the war, Cheryl Renée Gooch, author of “Hinsonville’s Heroes: Black Civil War Soldiers of Chester County, Pennsylvania,” wrote in her book. Isaac Amos Holingsworth, who served in the 127th, was treated by a doctor from Lancaster after his 1865 discharge, according to the book.

The Grand Army of the Republic Museum had hoped to sell the flag to the Union League or another museum before resorting to an auction, Waskie said. Funds from the sale will be used to either repair the museum building in the Frankford section of Philadelphia, which has deteriorated terribly, or move the collection to another location.