This category is for treaties that entered into legal force in the year 1991. For treaties that were written and opened for signature in 1991, see Category:Treaties concluded in 1991.
| Treaties by year of entry into force: | 1986 • 1987 • 1988 • 1989 • 1990 • 1991 • 1992 • 1993 • 1994 • 1995 • 1996 |
All items (4)