Why did Hitler ally himself with Non Aryan peoples like Italians, Romanians, and Bulgarians for example?

From what I understand, much of the Nazi party's political agenda was inspired by the Italian Fascist government, and Hitler was a great admirer of Italians, the Italian country and the legacy of the Roman Empire that Italy was known for, and also a great admirer of Mussolini. Italians were not of Aryan blood however, and if anything were probably closer ethnically to Jews/Eastern European/Slavic peoples than they were to Germans ( although a high percantage of North Italians were very nordic in appearance) However they were still not Aryans from what I understand. Even more so, Romanians who probably were even further apart from the Aryan race, and Bulgarians who were South Slavic, whom the Nazis hated almost as much as Jews. In the end, it seemed that Hitlers plan was to create an Aryan Masterace throughout Europe and eliminate anybody who did not fit this description. But if this was his plan, why did he ally himself with nations of Meditteranean/Slavic races like Italians, Romanians and Bulgarians?