N said, My Lord, indeed they have disobeyed me and followed him whose wealth and children will not increase him except in loss. And they conspired an immense conspiracy. And said, Never leave your gods and never leave Wadd or Suw or Yaghth or Yaq or Nasr. - N 71: 21-23
From the time of dam (a.s.) until 10 generations after, there was no shirk. The first act of shirk was committed by the people of N (a.s.).
Wadd, Suw, Yaghth, Yaq and Nasr were five righteous man. After their death, Ibls told the people to make idols in honor of them.
Generations later, Ibls deceived the people saying that the forefathers used to worship the statues and they were granted rain. Thus, the people started worship the statues.