It all starts with Suidobashi Heavy Industry's Kuratas piloted robot being unveiled.
https://youtu.be/uLl9mF8TSCUCopied from Know Your Meme:
"History
In 2012, Kuratas Suidobashi unveiled the first Kuratas robot, billed as “The World’s First Boarding Robot.” The robot was big enough for a man to sit inside and operate it from within, just as in the traditional mecha format. It was operated off of the XBox Kinect user interface, and while it couldn’t walk, it could drive on three wheels at about ten kilometers per hour. It could be armed with a series of cannons made for shooting fireworks or water bottles, and retailed for US $1,353,500."
THEN an American company called Megabots, Inc, made a kickstarter to raise $1.8m to fund a project to create their own mecha. The goal was to make 2 bots and an arena, and have them duke it out. The long term was to start a sporting league. They only got $65k, though, and they think it's because they had only a prototype turret at the time.
Eventually, however, they succeeded in making a robot, and made this video:
https://youtu.be/XVJTGLL2SnI5 days later, Suidobashi responds:
https://youtu.be/7u8mheM2HrgNo exact date is known, but the estimate of the fight is sometime in 2016.
As somebody in the comments says...
"Born too late to explore the planet
And born too early to explore the stars...
BUT BORN JUST IN TIME TO WITNESS THE BIRTH OF MECHA."