Sheriff of the huge Sacramento District before California became a state and organized county governments, George McKinstry Jr. was born at Hudson, New York in 1810, according to family sources. Educated in New York, either there or later McKinstry acquired some knowledge of medicine, but was a merchant when he settled in Vicksburg, Mississippi in 1839, where he became well acquainted with Pierson B. Reading. Reading emigrated to California in 1843, which may have inspired George to do the same in 1846, after struggling for five years with the chills and fever endemic to the Mississippi regions. McKinstry traveled most of the first stretch of the Oregon-California trail as a member of the large company initially led by William H. Russell which, over time and distance, separated into smaller companies. George complained to his trail diary that “the women and children were so much in the way,” but his recurring illness prevented his joining a single-men packing group until June 20th, when he left the main caravan to ride ahead on horseback to Fort Laramie with a few others—then, apparently ill again—rejoined the Hiram Ames company about June 24th, with whom he traversed the Hastings Cutoff behind the George Harlan train but ahead of the Donner Party. He reached Sutter’s Fort in mid-October 1846. His health too poor to permit him to participate in the Mexican-American War, George remained at the Fort, where he accepted Captain Sutter’s appointment as sheriff of the Sacramento District. As sheriff, McKinstry was involved in the rescue of the Donner Party in early 1847, chiefly through his fund-raising efforts. In late 1851 McKinstry moved to San Diego County, where he practiced medicine for several years from the home of John and Serafina Minter. When the Minters moved to Santa Ana George accompanied them, dying there about 1890.