According to records in Yorktown,the original Eckhardt ancestor in Texas was one Charles (probably Karl) Frederick Eckhardt who landed at Powderhorn about 1825. He & John York together founded Yorktown, Texas. So the story goes, he & York flipped a coin. If it came up heads, the town would be Yorktown & the main street Eckhardt street. If it came up tails, the town would be Eckhardtburg & the main street York street. John York & his only son were both killed by Indians shortly after the town was founded, but there are Eckhardts all over the area. Yes, there is an Eckhardt street in Yorktown.
There have been three Eckhardt families in Texas that I know of. The early one--the Yorktown/Fredericksburg group--my grandfather, George F. A. Eckhardt, who migrated to Texas in 1901 from New Orleans; and a family that migrated to Texas from Russia sometime after 1905. They settled around Kenedy. The original founder of Barth's cafe in Kenedy married an Eckhardt. I got to know her fairly well at one point, & she told me she was born in Russia in 1905 & came to Texas as an infant. There was also an Orville Eckhardt who was a pilot for Braniff a number of years ago, but he was originally from Pennsylvania.