The ancient Middle East was the story of one empire rising, falling, and being replaced by another. In 605 B.C., the Babylonians conquered Israel, taking many of its promising young men into captivity in Babylon. One of those men was Daniel.
When the lions' den event occurred, Daniel was in his 80s. Through a life of hard work and obedience to God, he had risen through the political ranks as an administrator of this pagan kingdom. In fact, Daniel was so honest and hardworking that the other government officials--who were jealous of him--could find nothing to remove him from office.
So they tried to use Daniel's faith in God against him. They tricked King Darius into passing a decree that during a 30-day period, anyone who prayed to another god or man besides the king would be thrown into the lions' den.
Daniel learned of the decree but did not change his habit. Just as he had done all his life, he went home, knelt down, faced Jerusalem, and prayed to God. The wicked administrators caught him and told the king. King Darius, who loved Daniel, tried to save him, but the decree could not be revoked.
At sundown, they threw Daniel into the den of lions. The king could not eat or sleep all night. At dawn he ran to the lions' den and asked Daniel if his God had protected him. Daniel replied,
"My God sent his angel, and he shut the mouths of the lions. They have not hurt me, because I was found innocent in his sight. Nor have I ever done any wrong before you, O king." (Daniel 6:22)
Scripture says the king was overjoyed. Daniel was brought out, unharmed, "...because he had trusted in his God." (Daniel 6:23)
King Darius had the men arrested who falsely accused Daniel, and along with their wives and children, they were all thrown into the lions' den, where they were immediately killed by the beasts.
Then the king issued another decree, ordering the people to fear and reverence the God of Daniel. Daniel prospered under the reign of Darius and King Cyrus the Persian after him.