Swedish publisher Paradox Interactive has delivered its best financial year in history. 

According to its report for the full-year ended December 31, 2020, revenue increased by 39 percent year-on-year to SEK 1.79 billion ($215.7 million), while operating profit rose by 33 percent to SEK 628 million ($75.7 million) over that same period.

New releases like Crusader Kings III and Empire of Sin contributed to that upswing, with the former setting new records for launch sales and concurrent players in the process.

Catalog titles like Cities: Skylines, Europa Universalis IV, Stellaris, and Hearts of Iron IV also played a key role, bringing in the majority of revenue during the fourth quarter along with Crusader Kings III.

Commenting on that performance, Paradox chief exec Ebba Ljungerud said it's clear the company's "proven strategy" of supporting established brands either by releasing add-on content or developing sequels was driving long-term growth.

"2020 was the best year in Paradox's history, with strong growth in revenue, profits and players. Our established brands continue to develop and grow with new players and new content, and the successful launch of Crusader Kings III in the third quarter gave us a further boost," said Ljungerud.

"Crusader Kings III broke several of our previous records at release, in terms of both number of simultaneous players and copies sold. It is a clear sign for us that we have succeeded in building on a brand through a sequel, which we will be able to further develop with new content for many years to come."

In terms of how Paradox has been coping with the ongoing COVID-19 pandemic, Ljungerud said the situation has had a "mixed effect" on its business -- citing an influx of players and rising sales at the start of the pandemic along with production difficulties and postponements.

"Our studio organization in particular has found it difficult to maintain the usual production pace. We have therefore chosen to postpone several planned but not communicated releases to ensure the right quality, which postpones the release dates during 2021," she explained.

"For us, it is crucial that our games are well received by the players, so we always choose, if possible, to give our development studios the time required to achieve our quality goals."

Ljungerud also commented on the troubled development of Vampire: The Masquerade - Bloodlines 2. Earlier today, Paradox removed lead developer Hardsuit Labs from the project and delayed the title indefinitely, and the CEO confirmed a new studio has already been hired to finish work on the game.