To bayesmarkobgauss:

Almost all pre-modern philosophy blurred the line between religion and philosophy.

And there are many philosophers from Africa. Probably the most famous African philosopher (especially in the West) is Augustine. The most famous 20th century African philosopher (and one of the most famous post-colonialism thinkers in general) is Frantz Fanon. One of the more famous pre-modern African philosophers is the Ethiopian Zera Yaqob (not to be confused with the emperor of the same name).

There was also a large tradition of wisdom literature in Ancient Egypt. The Book of Proverbs was influenced by it. The Eloquent Peasant could also be considered philosophy.

Also, the Inca definitely had philosophers, who were called amawtakuna.

To OP: there have been philosophers from all places. In addition to what the places I said, there are the Muslim Averroes, Avicenna, Ibn Arabi, Al-Farabi, Al-Ghazali; the Jewish Maimonidies, Ibn Ezra (Abraham), Qoheleth, Halevi, Philo; the Chinese Mozi, Zhuangzi, [Mencius] (https://en.wikipedia.org/wiki/Mencius), Zhu Xi, Huineng; the Indian Shankara, Nagarjuna, Kautilya, Abhinavagupta, Ramanuja; the Japanese Dogen, Ito Jinsai, Nichiren, Honen, Kukai. There are many more modern Eastern philosophers, I just tried to list mostly pre-modern. These people have also influenced Western philosophers. Schopenhauer and the transcendentalists liked Indian philosophy, Averroes and Avicenna were well-known in Medieval Europe, and Pythagoras is said to have traveled to Egypt.

Philosophy is not limited to Eurasia though. The Aztec tlamatinime had a rich tradition of philosophy, as you can read in Miguel Leon-Portilla's great book or here (EDIT: I just remembered, Nezahualcoyotl is one of the people mentioned many times in the book). Vine Deloria Jr. was a great 20th century Native American philosopher. There are also many books written on Native American philosophy that you can find, or I can suggest.

As for why you thought that, most non-Western philosophers have been ignored. This is the case for most non-Western artists and thinkers. The history behind this is modern European conceptions of European superiority (though this wasn't completely clear-cut, as Russians, Irish people, and Turks are European). And while it could be argued this superiority is still embedded in the consciousness, this legacy has left a tradition that makes it easy to stick with. Because of the language similarities, the numerous manuscripts, and the cultural familiarity, it's just easier for Westerners to stick with the same philosophers. It's creates a simple narrative, and its easy to digest, especially for younger students.

Some people have already given you more or less exhaustive lists of non-European philosophers, so my answer is going to be more philosophical than historical, just to make you think a little bit about the hidden assumptions of your question. First, you have to consider that you come from a time and place, so naturally, your knowledge will be, for the most part, limited to the things people around you read and debate. A XVth century Han Chinese would have probably wondered the same "Why is every author I read chinese".

Other reason is that those categories you use to describe social phenomena are often culturally specific and not really that universal. The way you probably think about what constitutes philosophy, is necessarily going to be based on those (time and place contingent) cultural products you label as philosophy. So, if for you philosophy is Hobbes or Locke-like, other forms of though, not similar to this, will seem unphilosophical to you. Is Borges philosophy or literature? and what about Nietzsche? or Buddha? So it's kind of like begging the question or a form of circular reasoning, it totally depends in the way you're defining it. For example, this happens all the time when people coming from monotheistic cultural backgrounds think of religion. All assumptions they make about what constitutes a religion fall appart when they try to apply this model to, for example, asiatic 'religions'. It does not fit well.

I agree it does seem like more are European, but I don't think it's quite as skewed as you do.

There are some historical American philosophers like Thomas Paine. The most famous philosophers confronting extremely modern issues like artificial intelligence and the nature of consciousness are all American (Thomas Nagel, John Searle) or Australian (David Chalmers).

A lot of Asian schools of philosophy blur the line between religion and philosophy. This means their ideas are less likely to be taught in western schools (too religious) or you just don't categorize them as philosophers. Arguably Confucius, Siddhartha Gautama, and Lao Zu should be on your list along with Sun Tzu.

I admit I can't think of any philosophers from Africa, South America, or Antarctica.