More info about the name "Niilo"
Niilo is a Finnish variant of Nicholas. Nicholas originates in Greek language and means "people's triumph". It has been a popular masculine given name for centuries and in different spellings all over the world. One of the famous bearers was Saint Nicholas, bishop of Lyra, who most likely serves as an inspiration for Santa Claus. In the United States, Nicholas has been frequently used for a very long time now.