Jan Hus started what later became the Moravian Church (another name for it: the Unity of the Brethren Church) when he rejected practices of the Roman Catholic Church in the late 1300's. He was burned at the stake in 1415 by order of the Council of Constance. After that, other Hussites rebelled, there was a Hussite civil war with some Hussites siding with the Catholics.
Finally the Hussites organized themselves as one of the first protestant churches in 1457. By the mid 1550's up to 90% of the inhabitants of the Czech lands were Protestant.
This is astonishing. My Czech ancestors are all Catholic. Most of the Catholic parish records are available and online, but the earliest available ones for my ancestors start in the 1590's. I've been doing a lot of research but have not gotten that far back yet! So, I hadn't really thought about the religious makeup of the Czech lands pre-1600's.
Probably a big reason for this is because I am not a skilled reader of dry history books unless there is an obvious human context. As my brother in law pointed out to me, it's the stories about real people that draw me in.
Anyway, the population, including the nobility, was mostly Protestant until the 1620 Battle of White Mountain. After this, protestants were forced to convert, executed or expelled. Catholic, German-speaking nobility took their place. The Brethren either operated underground or left. There are small communities in many places, notably in Pennsylvania.
These people are Moravians.
Here is a really fascinating digitized diary from a Moravian woman from the 18th Century, named Anna Marie Worbass. I enjoyed reading the translation. I think it helped me understand more about her faith than the dry history books.
Another meaning for "Moravian" is a person from Moravia. This is a historic region of the Czech lands. It was an independent state from Bohemia...until 1620...It is basically the Eastern half of the country. Silesia is a small sliver directly north east of Moravia. Sometimes you hear Moravia referred to as Moravia-Silesia. That is one of the names of the Kraj (regions) in the current Czech Republic.
Almost 100% of my Czech ancestors are from Moravia-Silesia, with my direct line hailing closer to the Silesian side.
In 2011, the Czech census showed a huge jump in regional self-identification, with more people saying they were, "Moravian" than ever before. Also, according to that same article, 15,070 people (!!) identified their religion as "Knights of the Jedi." Yes, as in...Star Wars...sigh.
I suppose it is possible to be a Moravian Moravian. Or a Moravian with Moravian heritage. I don't think I would self-identify as Moravian because...I am American. Also, that would be like saying all of my heritage is from my Grandpa Vasicek, which simply isn't true. But, I would proudly say I am a quarter Moravian.