Although skilful at managing Stalin's difficult personality, Beria was not immune to Stalin's paranoid suspicion.
As the power of the MVD grew, Stalin probably became concerned about Beria's ability to build up his own power base.
In 1951, Stalin ordered the arrest of a number of Mingrelian Party officials.
Beria himself was a Mingrelian and was close to a number of those arrested.
Mingrelians are a small ethnic group in Georgia.
Stalin ordered Beria himself to carry out the purge.
This was a classic Stalinist tactic to undermine the confidence and security of someone he felt could become a threat.
Stalin continued his pre-war policy of suppressing the rights and interests of national minorities in the USSR.
The top jobs in the non-Russian SSRs, such as the Party Secretaries and the police chiefs, went to Russians.
Centralised economic planning and control of collective farms was strengthened which reduced the ability of local communist parties to make decisions at a regional level.
Deportations of Estonians, Latvians, Lithuanians and Ukrainians were organised.
Hundreds of thousands were moved to Siberia and Kazakhstan.
Russian migrants were encouraged to settle in the depopulated areas.
The national cultures and identities of these states were downplayed at every opportunity and the Russian language was promoted through education and government.
These policies bore many similarities to the Russification pursued by the Tsars in the 19th century.