You are intensely misinformed.

First, there are no 'lesser gods" in Christianity.

Secondly, yes, there is a significant degree of merging between pagan holidays and Christian holidays in terms of calender, thanks in large part to Emperor Constantine's intentional doing - because he believed that it would help pagan Romans convert as he did, and because there is no date set in the Bible for Christmas and Easter anyway.

Third, Christmas trees and wreaths were a German tradition imported to Britain and then the rest of Europe and the world by Queen Victoria's German husband Albert, who merely thought it would be a pleasant addition to festivities. It took off because, well, it is indeed a very pleasant addition to festivities.

[By the way your criticism of the Trinity makes me even more certain that you are a Muslim. Muslims love to mock the Trinity because they can't get their inbred heads around the concept. Too complicated for them. They consider mocking the Trinity as 'pwning' the Christians, while the Christians just laugh at them while being thoroughly and correctly disgusted by their bloodthirsty moongod.]