Well, Chao Tó was Chinese General who founded Nam Viet or Nan Yue. The country existed from 207bc to 111bc. You know, the most important fact is Nam Viet was an independent country, Yes independent from Han´s China. Chao Tó became later King of Nam Viet and defended it against Han´s. With the successful Han´s invasion of 111bc Nam Viet eased to exist, and was incoporated into Han´s empire.
Baiyue is 100 Yue tribes. And we belonged to Yue´s. That´s it: Yue=Viet.
Wiki
"The Baiyue (Chinese: 百越; pinyin: Bǎiyuè), Hundred Yue or Yue (越
is a loose term denoting various partly Sinicized or un-Sinicized peoples who inhabited southern China and
northern Vietnam between the first millennium BC and the first millennium AD."