With Harold Camping's recent prediction about Doomsday being May 21, 2011, many people are being drawn to Doomsday theories. Doomsday theories date all the way back to the death of Jesus.  
 
In the year 156 AD, a man named Montanus declared himself to be the personification of the Holy Spirit, but was later declared a heretic. Since then there have been hundreds of Doomsday predictions that have intrigued and baffled numerous people.  
 
Though majority of Doomsday theories have religious backgrounds, the Bible clearly warns of the groundlessness of the specific predictions, as they are contrary to Matthew 24:36 "No one knows about that day or hour, not even the angels in heaven, nor the Son, but only the Father."  
 
Most prophets of doom tend to quickly gather their devotees whose belief is so fervent that they are willing to sacrifice their finance, family, and even their own lives. Who cares about anything when you can be sure that the end of the world is merely days away?  
 
Click on the slideshow to check out these 10 Doomsday aka End Time aka Judgment Day scenarios since the 20th century that haven't quite worked out, but has established those making the Doomsday predictions as false prophets.

Scientists announced that Earth would pass through the tail of Halley's comet in 1910. A discovery of comet tails that included a deadly gas called cyanogen in 1881 by an astronomer was brought into spotlight as the media covered the speculations about how everyone on earth could be bathed in deadly toxic gas, which resulted in a widespread panic across the USA.

Prophecy teacher Doug Clark published his new book in 1976 and claimed "The death of the United States and the birth of one world government under President Carter." He announced that President Jimmy Carter would be "the president who will meet Mr. 666, the Antichrist, soon."

In May 1980, Pat Robertson, a media mogul, televangelist, and Christian Coalition founder, astonished and bewildered many by announcing that he could guarantee that by the end of 1982 there was going to be a judgment on the world.

Vladimir Solovyev, eminent Russian theologian, foretold that in an upcoming war Japanese would win and conquer much of the world, but be defeated by the Europeans in the end. A brilliant writer and thinker would then arise and unite the world and especially all religious leaders. Then the Jews would accept him as the Messiah but only until they learn that he is not a Jew, which will result in the revolt in Jerusalem and the eruption of a volcano from the Dead Sea.   

Followers of the “Hyoo Go” (Rapture) movement, a collection of Korean "end-times" sects made much noise in 1992. They firmly believed that Jesus was coming in the air. When the prophesied events failed to pass, much turmoil broke out among the sects. On October 28 of the year all stations broadcasted the movements of the “Hyoo Go” sects live. After it came to pass out of their expectations, some believers were frantic, while others tried to attack their preachers with knives.

In 1997 rumors arose that an alien spacecraft was following the comet Hale-Bopp but it was kept a secret by NASA. Though the claim was refuted by astronomers, a San Diego UFO cult named Heaven's Gate was convinced that the world would end soon and 39 of the cult members committed suicide in the same year. The body of Marshall Applewhite, who was the leader of the cult, was found among the dead.

Nostrdame has enchanted many for over 400 years. His writings have been translated and retranslated in dozens of different versions. Many Nostradamus followers believed that in the seventh month of year 1999, a great king of terror will come from the sky.    

As the new millennium approached, many people became disturbed that computers would not be able to tell the difference between 2000 and 1900 dates. Many predicted catastrophic problems ranging from massive blackouts to nuclear holocaust, but January 1, 2000 began with yet another bright new morning.   

Ronald Weinland, God’s Church minister stated that  “by the fall of 2008, the United States will have collapsed as a world power and no longer exist as an independent nation.” in his book, 2008: God's Final Witness.  

Camping is president of religion-based Family Radio Worldwide of Oakland, California. He uses mathematical predictions applied to the Bible to predict dates for the end of the world. The most recent end time prediction is that the Rapture will be on May 21, 2011 and that God will completely destroy the Earth and the universe five months later on October 21.  

We will have to wait and see if Camping belongs on this list or not. However, it must be mention that Camping had earlier predicted September 1994 as the End Time but when nothing happened, he said he had made a miscalculation. Let's hope Camping is wrong again.