| Birth | 15 May 1852 | Pike Co., Illinois | | | |
| Census | 1 Jun 1860 | St. Mary's Twp., Hancock Co., IL, pg. 110; William T. Zumwalt, 8 (1851-52), born IL. | | | |
| Census | 1 Jun 1870 | P.O. Plymouth, St. Mary's Twp., Hancock Co., IL, pg. 18; William T. [indexed "S"] Zumwalt, 18 (1851-52), born IL. | | | |
| Marriage | 1 Jan 1874 | Hancock Co., IL - Leona May HUDDELSON | |  | |
| Census | 1 Jun 1880 | On same page as George Zumwalt. - Point Pleasant Twp., Warren Co., IL, ED 295 pg 21; William Zumwalt, 26 (1843-54), born IL both parents born IL, laborer. He, wife and son are in household of Lemuel Waggy (?) family. | | | |
| Census | 1 Jun 1900 | Tulare City, Tulare Co., CA, ED 66 Sh 4B; Wm. T. Zumwalt, head, born May 1852, 48, married 22 yr., born IL both parents born IL, farmer, rents. | | | |
| Census | 15 Apr 1910 | Tulare Ward 2, Tulare Co., CA, ED 202 Sh 10A; William T. Zumwalt, head, 56 (1853-54), marriage 1 of 30 yr., born IL both parents born IL, farmer. | | | |
| Census | 1 Jan 1920 | Tulare Ward 8, Tulare Co., CA, ED 223 Sh 5B; William T. Zumwalt, head, 66 (1853), married, born IL father born MO mother born IL, teamster - working out. | | | |
| Death | 21 Mar 1938 | California | | | |