I hope this is the appropriate place to post it in, if it isn't I'd be ok with deleting it!

My question involves the timeline of mummification. Actually, I have several questions about it. When did the ancient Egyptians start to use it? From whence did it come (were it's origins from another land or culture)? I have read that the later mummified bodies were found with only the most rudimentary techniques used, or it wasn't completed as fully like the cranial cavities left as they were. But I do not know when this started happening and they abandoned the old more formal mummification rites.

I am interested to learn why it went away along with the when! Thank you anyone who has some of this info.