When Gilbert Baker designed the rainbow flag in 1978, he did so to create a symbol and an icon for the LGTB community. A symbol, recognisable across the world, that people could use to express their pride.
Unfortunately, 40 years later, there are still countries in which homosexuality is persecuted, sometimes even by jail sentences, and in which the rainbow flag is forbidden.
Russia is one of these countries.
(There is an English translation to this story in the upper right corner of the link.)