[5][6] Robert Justus Kleberg Sr. (1803–1888), a Prussian settler, was born on September 10, 1803, in Herstelle, Westphalia.

Moseley Baker's company and subsequently served as one of the Texas guards for Gen. Santa Anna.

After the revolution, he volunteered for six months' duty in the Texas army in a campaign against the Indians on Escondido Creek.

When the Civil War broke out he raised a company of militia but because of his advanced age was not received into active service.

Their youngest son, Robert Justus Kleberg Jr. married Alice Gertrudis King.

His grave is marked by a monument in the form of a soldier's tent with the words "Remember the Alamo" carved at the base.

Kleberg County was named in his honor in 1913; a marker at his home site near Cuero was erected in 1936.

68.1% of the people in Kleberg County are religious: 37.3% are Catholics, 9.8% are Baptists, 8% are Muslims, 3.3% are Methodists, 2.7% are Pentecostals, 2.0% are Mormons, 0.9% are Lutherans, 0.7% are Presbyterians, 0.6% are Episcopalians and 2.8% are from another Christian faith.

Also, Kleberg County Attorney Kira Talip Sanchez was originally elected as a Democrat in 2014, but she announced in August 2023 that she switched parties and is now a Republican.

[16] Kleberg County has voted three times for either narrowly winning or losing Republicans (George W. Bush in 2000 and 2004, and Donald Trump in 2020).

The Riviera ISD portion is in the Del Mar College-Corpus Christi Junior College District.