- Red Sails: Tempest on the Steppes (Dragon #290)
- Red Sails: Sun and Earth (Dragon #290)
- Red Sails: Fell and Forelorn (Dragon #290)
- Rivers of Blood (Dungeon #89)
Dragon #290 also had an article on the city of Novgorod on page 76. It wasn't labeled "Red Sails" but it was a useful addition to the setting.
I originally believed that these were supposed to be tied to the Vikings and Charlemagne's Paladins Sourcebooks from the AD&D HR series. However, I am not sure if there was ever a specific connection between the articles and the books?
Red Sails was 3rd edition and the two books you mention were 2nd edition, so the only connection is that they both depict roughly the same time period and the same planet.
What about other articles that could connect to the HR series
Dragon #257 included an article called "Dark Ages" by Ian Malcomson, a very well-done campaign setting detailing Saxon Britain from the time of the Saxon conquest to the time of the Norman conquest. It tied very closely to the Vikings Campaign Sourcebook
There was a follow-up article by the same author in Dragon #263 called "Hearth & Sword," detailing the Saxon gods (which aren't exactly the same as the Norse gods).
Ian Malcomson also wrote an article called "Steal from the Rich" in Dragon #274, detailing a 3rd edition campaign setting based on Robin Hood. You might tie that into HR7 The Crusades
For more Russian fantasy, I suppose you might also look at "The Dancing Hut," an adventure by Roger E. Moore that was published in Dragon #83 (March 1984), and the "Demonomicon of Iggwilv: Kostchtchie" article in Dragon #345 (July 2006). The Dancing Hut of Baba Yaga
was also a 2e adventure.
Paul Leach also wrote two articles in Dragon after the release of Red Sails. One called the Thane (#323) and one called Viking Raider (Dragon #337). Does anyone know if these were connected to Red Sails at all?
The thane is a variant fighter class, "professional fighters sworn to protect a clan or tribal chieftain." It would work well enough in a Red Sails campaign, but there's no explicit connection.
The viking raider article gives a little historical background on historical vikings and provides a new feat, Seafarer. You could use it in a Red Sails campaign, but again there's no explicit connection. The article suggests you could use it in a historical campaign or to represent Greyhawk's Frost Barbarians or viking types from the Forgotten Realms' Sword Coast.