— Sam Allen
He grew up in Benson, Arizona, and lived there with his wife and child.
The Long War
In spring 2040, while he was on the USS Benjamin Franklin, one of their assignments was located in the town of Reboot, in a stepwise New York State on Earth West 101,754. A small group from the twain went down, including Lieutenant Sam Allen, in charge of the marines.
Once there, they realized that their equipment was dropped on Earth West 101,752 and had no way to know where the town was or even catch up with the Franklin since none of them brought their Stepper with them. Luckily, they ran into Bill Lovell in the forest and finally reached Reboot.
While he was there he asked an inhabitant of the town, Jack Green, to rent out a room in his house to Ensign Toby Fox, who was working on a census and would need somewhere to stay while gathering his data. Jack Green refused to accept their money, arguing that they use favours in Reboot and expressing his despise of the Datum government, and so Allen attemped to arrest him but was stopped by Nathan Boss, in charge of their party.
The Long Mars
Between 2030 and 2040, in Happy Landings, a group of Next now known as the 'Napoleons' offered their leadership to the community's elders but got rejected. They attempted a coup d'état but their reign didn't last long thanks to the USS Neil A. Armstrong I. The elders then requested Captain Stringer to bring the 'Napoleons' aboard as prisoners to exile them in a remote Long Earth from where they wouldn't be able to come back from.
Aboard the ship, they manage to seduce most of the crew to the point where a fight occured between them and the rest led by Captain Stringer. They eventually won and took control of the ship and dumped everyone else oustide the ship (even their followers) except Sam who was hidden in the Armstrong's envelope at the moment.
It was Sam, now a captain, who provoked the crash of the ship on Earth West 182,674,101 where he lived for several years as a prisoner to the Next until he was found by Snowy, who is part of the crew of the USS Neil A. Armstrong II, in 2045.