William Vandervoort was born around 1820 in Ohio. He married Teresa Harvey, and they had at least six children: Paul, born on July 12, 1846; Cyrus, born around 1851; Mary, born around 1858; Warren, born around 1861; Henry, born around 1869; and Lewis, born around 1869. They lived in Towanda, Illinois, and he worked as a farmer.
He supported the Union war effort during the Civil War. In March 1863, he declared that he would "like to see those infernal Copperheads cleaned off from the face of the earth. I do not consider that they are fit to live and enjoy the privileges of great and free people. They ought to be banished to Africa and compelled to live under some petty king." By 1870, he owned $1,500 of real estate and $825 of personal property. By 1880, he was working as a school janitor. His wife died on October 9, 1885, and he moved to Omaha, Nebraska, the following year to live with his sons. He died in Omaha on October 3, 1888.