Why is there Violence in the Old Testament?

When we look at the New Testament, we see such a loving and caring God. All we have to imagine is the cross, all His miracles, and how God cared, loved, and healed the people. However, when we look at the Old Testament, we see a very different God: a violent God that seems to like wars. Therefore, we tend to ask ourselves: is the God of the Old Testament the same as today’s?