Death Eater activity during theFirst Wizarding Warconsisted of attacks onwizards and witches, and large numbers of Muggles. These were initiated by the Death Eaters often, but not always, on the orders of Voldemort. When the Ministry did not suffer an ostensible collapse in the eleven years of Voldemort's reign, the Death Eaters began to attack prominent wizarding families. As a result, fear gripped the wider wizard community, but the Death Eaters remained opposed by the Order of the Phoenix, founded byAlbus Dumbledore.
At the height of the war,Severus Snape reported to Lord Voldemort the part of the prophecy he had heard while listening in on a conversation between Dumbledore and Sybill Trelawney which predicted that either Harry Potter, the son of Order members James and Lily Potter, or Neville Longbottom, son of Order members Alice and Frank Longbottom, would be the one to destroy Voldemort. Voldemort attacked thePotters personally, seeing them as a greater danger to him. Despite being under the protection of the Fidelius Charm, Voldemort was able to get into their home because James entrusted his old friendPeter Pettigrew was Secret-Keeper, and Pettigrew subsequently betrayed the secret to Voldemort.
Snape failed to overhear the entire prophecy, including the announcement that Voldemort himself would mark his own equal. Although Voldemort killed James and, despite Snape's pleas that she be spared, Lily, theKilling Curserebounded off Harry and hit Voldemort, destroying his living body. However, due to his extensive performance of Dark magic, Voldemort's soul survived and escaped.