The first day of Passover in 1836 was April 2nd.
All over the world.
The battle of San Jacinto happened in present-day Harris County, Texas.
Officially it was the year after they left Egypt, but it wasn't celebrated.
Yes, they absolutely can. Since passover is seven days (or eight in the diaspora) it must occur at least once.
It was part of the Exodus from Egypt and was commanded by God. See Exodus ch.12.
In 2010, Easter Sunday was the 6th day of Passover. Those often seem to occur close to one another. Wonder why that is.
Shevuos is about six weeks after Passover. If Lag BaOmer counts, then about two weeks after Passover is Lag BaOmer.
49 The seventh Sunday after Easter, commemorating the descent of the Holy Spirit upon the disciples.
Burnt offerings and it occured during religious times like the passover.
Ishtar is a pagan fertility goddess whose rites occur in Spring, close to Passover. While the "holidays" were combined by the Catholic church, many sects do not recognize the blending of Ishtar worship with Passover.
1836
It was founded in 1836.