In a first-season episode Adams says the war has been over for five years (suggesting the first season takes place around 1870, although, in "The Major Adams Story", part 1, it is clear that Adams had taken trains west in previous years, commencing "as soon as the war was over"). In season two, reference is made to the war ending six years earlier (1871) and to the presidential nomination of Ulysses S. Grant (1868), a neighbor of Adams before the war and eventually his commanding officer. In "The Jenna Douglas Story" (season 5, episode 6), and again in "The Heather Mahoney Story", the year is clearly stated to be 1868 (this is more problematic since these are John McIntire/Chris Hale episodes). In "Little Girl Lost" (season 8, episode 12), Charlie states that the year is 1869. In season three (in "The Vincent Eaglewood Story") Grant and Colfax are identified as the current President and Vice President of that time, which dates it as Grant's first term (March 1869 to March 1873); but also in season three (in "The Countess Baranof Story") the storyline involves the impending sale of Alaska by Russia, but that transaction actually took place in 1867, by Secretary of State William Seward under 17th President Andrew Johnson. "The Bernal Sierra Story" (first season) made extensive reference to the ongoing revolution in Mexico pitting republic president Benito Juárez against Maximilian I of Mexico (aka Emperor Maximilian installed by French emperor Napoleon III)--but that uprising ended decisively with Maximillian's capture and execution in 1867. Also in season three, an adventure involving the Mexican revolution led by dictator Porfirio Díaz, which began in 1871 ("The Stagecoach Story", season 3, ep 1, broadcast Sept 30, 1959). "The Cathy Eckhardt Story" (fourth season, broadcast November 9, 1960) clearly shows the year is 1870, but in "The Charlene Brenton Story" (late third season, broadcast June 8, 1960) reference is made to Bill Hawks' having read the novel Ben-Hur, which was not published until a decade later in 1880. "The Sam Pulaski Story" (Season 7, episode 8, broadcase November 4, 1963) misplaces Hell's Kitchen as the Brooklyn waterfront instead of the real location on the west side of mid-Manhattan, and dates the story as 1868 although the name "Hell's Kitchen" was not used for that neighborhood until years later. The First Transcontinental Railroad was completed in 1869, following approximately the same route as a wagon train from St. Joseph to Sacramento. This would have made wagon trains obsolete by the time most episodes in the series take place in the 1870s; however, little reference is made to railroads in the West during the series.