Can you believe….the Roman Catholic Church is not THE Catholic Church.  It is an autonomous or sui juris (of one’s own right) church like the Eastern Churches…in union with the bishop of Rome!  It is that “union with the bishop of Rome” which is the tie that binds ALL the autonomous churches together.

“The Latin Church is an autonomous or sui juris particular church in communion with the Catholic Church. There are several such sui iuris particular churches within the Catholic Church. Other examples are the Maronite Church, the Ukrainian Greek Catholic Church, and the Syro-Malabar Catholic Church. They differ from each other in liturgy (ceremonies, vestments, chants, language), devotional traditions, theology, canon law, and pastors (even if in the same territory as another), but they all hold the same faith, and all see union with the bishop of Rome, the pope, as essential to being a Catholic.

The Latin Church is the largest of these sui juris churches, with a membership far greater than all the others taken together. It arose in Western Europe and North Africa, an area once encompassed by the Roman Empire, throughout which Latin was widely understood and spoken. It is sometimes called the Western Church. All the other sui iuris particular churches, of which there are 23, originated farther east and are, therefore, collectively known as the Eastern Catholic Churches. Because of the facility with which people can nowadays take up residence in a different country, members of all of these sui iuris particular churches are no longer confined to their areas of origin and can be found all over the world.”

Excerpt from:  https://en.wikipedia.org/wiki/Latin_Church with footnotes from Modern Catholic Dictionary and other Catholic sources.