There is no nudity, but some low-cut dresses, especially at the formal dinner in the middle of the series.
Violence & Gore
Mild
Near the beginning, the mill owner beats and kicks a worker for smoking on the job until he is bleeding.
Another scene, a woman gets hit by a rock thrown by rioters. A trickle of blood is on her head and she is knocked unconscious.
Also, rioters were being hit with clubs by mounted men to disperse them.
There is a violent confrontation between two characters where they exchange yelled insults and pushing or blows.
Alcohol, Drugs & Smoking
Mild
Worker with a pipe at the beginning, smoking at the mill. Mill owners smoking at a dinner and at their club. No drug references but alcohol consumed at dinners and club. John Thornton takes a drink after his proposal is refused.
Frightening & Intense Scenes
Moderate
Two different times dead men are shown, once in a morge and another is brought home carried on a board and uncovered to show his wife after he drowned himself.
Another woman is shown taking her last breath surrounded by her family.
A father comes home to find his grown daughter dead and takes her in his arms and cries.