For years, wolf conservationists told people "there has never been a documented wolf attack on a human in North America". This was a lie!
The key phrase is "documented attack", which means:
-the wolf has to be killed, examined and found to be healthy
-it must be proven that the wolf was never kept in captivity
-there must be eyewitnesses to the attack
-the person must die from their wounds
Of course the public was never informed of this. There have been many cases of wolves killing people in North America that were reported in 19th and 20th century newspapers (here's one example) but since they did not meet this strict definition, they were all ignored.
Again from Wikipedia:
"Skepticism among North American scientists over the alleged ferocity of wolves began when Canadian biologist Doug Clark investigated historical wolf attacks in Europe and, based on his own experiences with the relatively timid wolves of the Canadian wilderness, concluded that all historical attacks were perpetrated by rabid animals, and that healthy wolves posed no threat to humans.
Although his findings were later criticized for failing to distinguish between rabid and predatory attacks, and the fact that the historical literature contained instances of people surviving the attacks at a time when there was no rabies vaccine, his conclusions were nonetheless adopted by other North American biologists.
This view subsequently gained popularity among laypeople with the publication of Farley Mowat's semi-fictional 1963 book Never Cry Wolf, with the language barrier hindering the collection of further data on wolf attacks elsewhere. Although some North American biologists were aware of wolf attacks in Eurasia, they dismissed them as irrelevant to North American wolves."
There have been many cases of wolves attacking humans outside of North America. In one famous medieval incident 40 wolves ran through Paris devouring people before they were cornered and killed in front of Notre Dame. In medieval Russia thousands were eaten by wolves.
Wikipedia says 7,600 people were killed by wolves from 1200-1920 in France - an average of 10.6 per year. In one area of India, 721 people were killed by wolves in 1875. In 1878, 624 people were killed! It's not only in times past - from 1980-1986, 122 people were killed in Hazaribagh, India, and between 1989-1995, wolves killed 92 people in southern Bihar. Many more examples from many more countries but I don't want to make a giant block of text.
Are North American wolves somehow different? I don't believe so. In 2005 an official Canadian inquest found that 22-year-old student Kenton Joel Carnegie was killed and eaten by wolves in Saskatchewan, and in 2010, wolves attacked and killed Alaskan teacher Candice Berner.
In my opinion this myth of "no wolf attacks" is not based on facts or common sense, it was a construction designed to give wolves a more positive image so the public will support pro-wolf initiatives.