One challenge with online gaming is the high turnover rate of players. I rarely run a session without a new player. I try to create a campaign with a specific feel. I created a history of the world establishing major plot lines.
There are many ways to bringing a new player into the campaign. When playing around a physical table, the group of players is normally static. The players normally warn the dungeon master when a new player will be attending. This allows the dungeon master to work out a situation where the party meets the new character. The dungeon master can provide the new player an overview of the campaign. The dungeon master hopes the player will read the overview. With online playing, it is common for a player to join at the last minute.
I frequently have new players who have never used Dungeons and Dragons fourth edition. I started out with the original Dungeons and Dragons in the white box. I remember the first game I played. We started playing about 6:00 PM in the evening and ended around 7:00 AM. It took about an hour for the three of us to create our characters.
Spending an hour a session to create new characters and introduce the setting would really slow down online gaming. I feel players today want to spend about as much time creating a new character as they do when they create a new character in Skyrim or Mass Effect 3. They want to jump into the action.
This is my personal conflict. How do I introduce new characters to a complex campaign quickly without losing the feel of the campaign? I tried a few session where I designed scenarios for the new characters to join the party. In one session, the party found the new players locked in cages. I developed a back-story how a faction in the campaign captured, bound, hooded, and gagged the new characters. The faction then threw the new characters into cages. This worked because the party was exploring a dungeon. I prepared by setting up rooms specifically for the new characters. The party had not explored three directions in the dungeon. I set up conditional rooms in each of those directions and hoped the party would not backtrack and go some other way.
Constructing scenarios to introduce new characters is more effort than it is worth. The character may only play one session then leave. The simple solution is the new characters materialize as part of the party. No introduction. They just start playing. The players introduce their characters to the rest of the party. That works but does not introduce the history campaign.
For several sessions, the first thing I did was provide an overview of the campaign. I intended to create a video on YouTube introducing the campaign. The problem is will the new players actually prepare for their first session? Based on my experience over the last year I thought it unlikely all the players would spend the time preparing. I know some would. I also know some would not.
Now I just start the session. I give a brief overview of the current situation. I let the other players introduce the situation from their viewpoint. I only give a history when it affects the play of the game. This follows the classic epic convention of being in medias res. In Medias Res is Latin for "it begins in the middle of things" and then has flashbacks to explain action leading up to that point.
At first, starting without the backstory seemed contrived in roleplaying. However, it actually adds to the feeling of "being a stranger in a strange land". Player can start the campaign and learn through on-the-job training.