To start it off...

In September, 2005, a Danish newspaper- Jyllands Posten- published 12 editorial cartoons, most featuring the Muslim Prophet Muhammad. The cartoons were reprinted in over 50 countries around the world, and Chaos ensued, with the nation of Islam (in particular, the extremists) threatening violence and death against the cartoonists and the newspaper as a whole.
The Islam world recognizes their prophet as someone who can be described written and orally, but Muslims have been explicitly prohibited from creating visual depictions of him.

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