Was Hitler the Antichrist of biblical prophesy?

No. The Bible defines Antichrist as someone who denies that Jesus has come in the flesh (2 John 7): "For many deceivers have gone out into the world, those who do not acknowledge Jesus Christ as coming in the flesh. This is the deceiver and the antichrist" (also see 1 John 2:22). There were a number of antichrists ("deceivers") in John's day. In fact, he states, "Children, it is the last hour; and just as you heard that antichrist is coming, even now many antichrists have arisen; from this we know that it is the last hour" (1 John 2:18). The presence of these antichrists led John to the conclusion that it was "the last hour." This is a refernce to the prophetic events that were on the horizon, namely the destruction of Jerusalem that took place in A.D. 70. John is not describing a distant political figure Ike a Hitler or Mussolini; he had certain people in mind who were alive when he was writing and held certain theological opinions about Jesus. You will notice that Revelation does not use the Word "antichrist." Also, there are no verses in the Bible that teach an antichrist will rule over the world for seven years. In fact, the phrase "seven years" does not appear in Revelation. The use of Daniel 9:27 as evidence for a distant future antichrist is untenable. It's Jesus who makes a covenant with His people: three years of ministry and three years of gospel proclamation before the gospel goes to the nations (Acts 10).