The Gauleiter were regional Nazi party leaders. Speaking to large audiences was in the job description. I'm beginning a new page of translations of speeches by various Gauleiter. At the moment, the only items are speeches by Julius Streicher, which were already on the GPA, and a February 1939 speech by Josef Bürckel, who had just been appointed Gauleiter of Vienna
I expect to add other speeches over time. Should you happen to have a reliable speech text by a Gauleiter, I'd surely appreciate a copy (although I cannot predict how long it will take me to get to translating it).