Why did the people of Egypt make their kings into mummies?

To understand the answer to this, you should realize that
it was not only the kings who were mummified.  Thousands of mummies have been found, not
all were kings.  Basically, anyone who could afford to be mummified, was.  The reason
for this was because the Egyptians felt that being mummified was necessary in order to
have a good afterlife.  They believed that only people whose dead bodies were well
preserved could really have a complete life in the world that comes after
death.

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