Before the printing press was invented in 1453 by Gutenberg, the Catholic Church was the chokepoint of knowledge in Europe. It produced all the written knowledge in its monasteries, and anything circumventing that chokepoint had to rely on inefficient oral tradition and transmission – people telling each other across generations and across distance, essentially playing Telephone. The Church also wrote all its knowledge in Latin, which wasn’t readily accessible by the common folk, and so even needed the local preachers to translate the knowledge into the local language.
The printing press wasn’t as much a new invention, as it was the extremely successful combination of four other inventions: movable metal type, cheap clothrag-based paper, oil-based inks, and the squeeze press; along with a few auxiliary inventions, like the Gutenberg hand mould that allowed for rapid fabrication of metal movable type and therefore profitability.
Paradoxically, Gutenberg was convinced the press would strengthen the Church, as it would reduce copying errors between Bibles significantly – all books would indeed be identical. The result was the exact opposite, much thanks to the footwork of one Martin Luther, who objected to some abuses of power by the Church – abuses enabled by their chokepoint on information and media at the time. Specifically, they were selling salvation to raise funds, something that wasn’t in the books – and being a clergyman, Luther knew this and objected to it.
The objection of this one man sparked a century of civil war across the known world at the time – loosely described as the years 1524-1648. In particular, it was triggered by the Luther Bibles, where Luther printed bibles in German and French, and distributed them by the cartload — instantly revoking the media chokepoint previously held by the Catholic Church, an action that upset the power balance so much it led to a century of brutal warfare.