The young Rosenberg graduated from the Petri-Realschule (currently Tallinna Reaalkool) and went on to study architecture at the Riga Polytechnical Institute and engineering at Moscow's Highest Technical School completing his PhD studies in 1917. During his stays at home in Tallinn, he attended the art studio of the famed Painter Ants Laikmaa, but even though he showed promise, there are no records that he ever exhibited. During the German occupation in 1918, Rosenberg served as a Teacher at the Gustav Adolf Gymnasium. Rosenberg held his first speech on Jewish Marxism at the House of the Blackheads on 30 November after the outbreak of the Estonian War of Independence. He emigrated to Germany with the retreating imperial army, along with Max Scheubner-Richter, who served as something of a mentor to Rosenberg and to his ideology. Arriving in Munich, he contributed to Dietrich Eckart's publication, the Völkischer Beobachter (Ethnic/Nationalist Observer). By this time, he was both an antisemite – influenced by Houston Stewart Chamberlain's book The Foundations of the Nineteenth Century, one of the key proto-Nazi books of racial theory – and an anti-bolshevik. Rosenberg became one of the earliest members of the German Workers' Party – later renamed the National Socialist German Workers' Party, better known as the Nazi Party – joining in January 1919, eight months before Adolf Hitler joined in September. According to some historians, Rosenberg had also been a member of the Thule Society, along with Eckart, although Nicholas Goodrick-Clarke contends that they were only guests. After the Völkischer Beobachter became the Nazi party newspaper in December 1920, Rosenberg became its Editor, in 1923. Rosenberg was a leading member of Aufbau Vereinigung, Reconstruction Organisation, a conspiratorial organisation of White Russian émigrés which had a critical influence on early Nazi policy.