George Nelson Chalker was born on July 14, 1842, in Unadilla, Michigan, to Otto Chalker and Mary Lee. His father was a farmer who owned $1,500 of real estate and $560 of personal property by 1860. He grew up and attended school in Unadilla, until the 1850s, when the family moved to Locke, Michigan. By 1860, he was working as a farmhand.
Chalker enlisted in the Union army on August 6, 1842, and he mustered in as a private in Company B of the 26th Michigan Infantry on September 15. The regiment took part in the Battle of the Wilderness, the Battle of Spotsylvania Court House, the Battle of Cold Harbor, the siege of Petersburg, and the Appomattox campaign. He was wounded at Hanover Junction, Virginia, on May 24, 1864, but he eventually recovered and rejoined the regiment. He mustered out on June 4, 1865.
Chalker may have settled in Illinois after the war, and he married Susan Lamb there on February 1, 1870. Later that year, they were living in Flint, Michigan, and Chalker was working in a sawmill. They moved to Clinton, Iowa, in the early 1870s, and their son Clark was born there around 1873. He applied for a federal pension in May 1892 and eventually secured one. By 1900, he was working as an “ice and coal dealer” in Clinton, and he employed at least one white servant. He retired sometime in the 1910s, and he died in Clinton on February 20, 1920.