The 1st century AD was a period in history that began with the year 1 and ended in the year 100. It is notable for the rise of the Roman Empire, which expanded its territories across Europe, North Africa, and parts of Asia. This century also saw the spread of Christianity, which began with the teachings of Jesus Christ and the work of his apostles. During this time, significant advancements were made in various fields, including architecture, literature, and science. The construction of iconic structures like the Colosseum in Rome and the writings of historians such as Tacitus and Josephus contributed to the cultural legacy of the era.