Hey there!
Because introductions are meant to hook in your audience and introduce your topic so that the readers have a sense of what topic you are writing about, here are some suggestions:
"Sacrifices have been a part of human history for a long time..."
"When most people hear the term 'sacrifice' many people think of...while this may [or may not] be true, sacrifices..."
Hope this helps you get started on your essay! :)