Rugby in Russia developed waves.
The first wave was before World War 2. There were 3 of mass games sports in Russia (football and rugby in the summer, Russian hockey - winter). These sports were sharing the same stadiums, in '38 to derby Loko - Spartak at Lokomotiv stadium in Moscow was 50,000 spectators. After World War 2 rugby banned in the Soviet Union - the reason that this kapitallistic sport, although in Russia played a similar game (Kila) for many centuries, but the commies did not know it.
From the 60s to the 90s was the massive development of the rugby. National team of Russia (USSR) was №6 in Europe in the 80s, was founded about 200 clubs, many leagues, we were invited to the 1 World Cup 87, there have been calls for the inclusion of USSR in '95 in 6 Nations but...
Then 90 years - the biggest economic and politic crisis, the country plundered liberals, rugby has been in decline, only the last 10 years has gone new growth - established professional league (10 clubs), there are 2 division, the federal amateur league.
By the way, the attendance record was set at the rugby at Luzhniki stadium - 104,000 viewers on game Spartak - Khimki (1962).