What significant action did Hitler take in his first year in power to challenge the Treaty of Versailles?

In his first year in power, Hitler's significant action that challenged the Treaty of Versailles was the initiation of secret rearmament. The Treaty of Versailles, signed in 1919 after World War I, imposed strict limitations on Germany's military capabilities, including restrictions on the size of its army and a ban on the production of weapons. By secretly rearming, Hitler was fundamentally undermining the treaty's terms and demonstrating a willingness to restore Germany's military strength.

This rearmament served multiple purposes: it aimed to boost national pride among Germans, restore confidence in the Nazi regime, and prepare the country for future expansionist ambitions. This covert buildup was a bold defiance of the international community, which had established the treaty as a means to ensure lasting peace, and it laid the groundwork for Hitler's aggressive military policies in the years leading up to World War II.