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Bahrain entered into a treaty of protection with the United Kingdom in 1861. It became independent state in 1971. Bahrain has used a variety of stamps: 1884 to 1933 - Indian stamps; 1933 to 1948 - Overprinted Indian issues; 1948 to 1960 - Overprinted British issues; From 1960 - Its own designs.
Inside #206-9: Pseudo Stamps
60th Anniversary of the 1st stamp of Bahrain
Inside #????: Bahrain stamp for local use (1953-57)
Best website related:
Bahrain Philatelic Bureau Postal Directorate