29 January 1942: Great Britain and Soviet Union sign treaty of alliance with Iran, wherein Iran agrees to remain [[neutral]]; Britain and USSR promise to withdraw their troops from Iranian territory 6 months after hostilities with Axis cease. (Persian Corridor is to become principal route for movement of supplies to USSR.)<ref>[https://history.army.mil/portals/143/Images/Publications/catalog/11-1.pdf p. 21.]</ref>