What role did cats play in ancient Egypt?
Both domesticated and wild cats lived amongst the ancient Egyptians. Cats were associated with good night vision and with catching mice and snakes, traits that led to association with certain gods.
Cats were also associated with lions, and both animals were identified for their motherly instincts. For instance, the protective mother goddess Bastet was often depicted as a cat or with the head of a cat.
There were several lion-headed or lioness goddesses as well, including Wadjet, Mut, Shesemtet, Pakhet, and Tefnut.
Because of cats' mythological associations, cat fur, feces, and fat was used in medicine or in magic, while small cats were also used as symbols of fertility and sexuality. They had a lot of roles and associations in Ancient Egypt!
Were the cats sacrificed? Or did they just die?
Both. Most cats that were mummified to be offered to Bastet and other feline deities were sacrificed for the occasion. Some cats, especially family pets, would have been mummified after they died of some other cause.
Were the cats dead prior to mummification or sacrificed for entrance into the afterlife?
The simple answer is, it depends. Many cats and other animals were sacrificed in order to send their souls to the afterlife. This likely represents a larger proportion of cat mummies.
There is also evidence that pet cats were mummified after having died of natural causes.