The difference between the Catholics and the other Christians

Many don't understand the difference between the Catholics and the other Christians mainly the Orthodox.

As a history student and fan, I will explain it from the historical perspective without any moral judgements against anyone.

In the West, specifically before the rule of Charlemagne, the Catholic Church was just another orthodox church with an important status because of its location in Rome (Latin: primus inter pares – meaning first among equals).

After the rule and the coronation of Charlemagne, the Catholic Church started to take form over the many centuries.

In 800 Charlemagne was crowned emperor in Rome by Pope Leo III.

The East–West Schism, also known as the Great Schism or the Schism of 1054 finally happened after two centuries.

The Pope decided that the East (the Eastern Roman Empire aka the Byzantine Empire) should acknowledge his authority over religious matters (and political as well since there was no separation between the two during this time). He decided to excommunicate the patriarch of the Eastern Roman Empire believing that they will submit. This heavily backfired.

The rest was history. The biggest difference between the Catholics and the Orthodox finally manifested. The Catholics saw the Orthodox as heretics for not acknowledging the Pope. The Orthodox saw the Catholics as heretics for making innovations within the Christian Faith and its traditions.

And then, we saw the Protestant Revolution after the invention of the printing press because of many criticisms against the Catholic Church and the sale of indulgences as well as other disagreements.

Basically, you need to have a Pope. At least, that's what history tells me. It seems so ridiculously obvious. What do you think?