Because when you didnt have a camera the only thing to do was paint a portrait of something to show what it is and show where it was.
Rembrandt painted portraits, van Gogh painted over sixty self portraits.
As part of record keeping
No, it was not.
Hans Holbein the younger traveled around painting portraits.
She painted many landscapes. Practically no portraits.
If you mean Rembrandt, he painted or drew about 30 self-portraits.
They had their portraits painted.
Holbein
Rembrant
He painted landscapes, portraits and still life.
Yes, he painted quite a few self portraits and drew some.
Rembrandt painted three or four self portraits in 1669..