A New Home
Survivors of Haven and people from all over Thedas flock to Skyhold. Cassandra addresses you and decides to name you the leader, the Inquisitor! Your dialogue choice here greatly affects approval for most companions.
An Old Friend of Varrics
You'll have a conversation with the group and Varric mentions a friend. This friend is a well-known person from Dragon Age II, who you should be very familiar with and he would like you to meet them on the battlements. In short, this friend has a Warden friend (different depending on your world state) in Crestwood and that's good because you can find out if the Grey Wardens have truly gone missing and where. If you speak with Cassandra she'll blow up at Varric but you can try to work it out later.
You had the chance to recruit one of them earlier based on your choices, but the other should be hanging around Skyhold. Be sure to talk to him and recruit him if you want. And why wouldn't you want to add to your merry band of misfits?
Specializations for the Inquisitor
Be sure to visit the War Table and start this mission. You'll have three advisors come to Skyhold allowing you to pick one Specialization. You will have to gather a few things for each advisor to receive the Specialization you want. All of your companions have taken on their Specialization at this point. Also, pick up the Arcanist from the War Table so you can craft runes.