God's timing is always perfect.
It was no coincidence that Jesus was born during Pax Romana - a long period of relative peacefulness throughout the Roman empire. In order to maintain their sprawling empire, the Romans built an extensive system of roads making it easier to communicate, and for their troops to travel. This also meant that news about Jesus' life, death, and resurrection would be able to spread quickly throughout the vast empire.
John the Baptist prepared the way for Jesus. In Rome, important officials were always preceded by an announcer. This is why the book of Mark, which was written to Roman Christians, begins with John the Baptist - the herald of Jesus Christ.
John preached in order to prepare people to accept Jesus as God's Son, challenging them to confess their sin individually. People who don't know Jesus nowadays, also need to be prepared to meet Him. They need to admit that they need forgiveness before they can accept it. And, of course, their hearts need to be softened. We need to pray for the unbelievers around us, that God would soften their hearts, and prepare the way for Jesus.
Tomorrow's Bible In a Year Passage: Leviticus 25; Mark 1:23-45