"Shadow of the Past" is a popular title used across several major games and media. Since you didn't specify which one you're looking for, I've summarized the most likely guides for you below.
: Go to the Gallivan Embassy (fast travel from Sunblaze Court) and speak with the guard to meet the senior deputy.
In this game, "Shadows of the Past" refers to challenges that relive the memories of Celebrimbor. Shadow of the Past
This is a main quest where you deal with political intrigue at the Gallivan Embassy.
: For specific missions like Breged , use Ranged Mode or Wraith Mode to slow time and see hidden mines on the ground. Solasta: Crown of the Magister "Shadow of the Past" is a popular title
: You'll eventually infiltrate the New Empire Embassy through a sewer hole near Gravekeep’s Cask to switch out documents. The Lord of the Rings: LCG (Card Game) A guide for the first scenario of the LOTR Saga expansions.
: Build up your Wrath by countering and fighting enemies normally. Once full, activate Elven Rage to use unlimited insta-killing arrow attacks. In this game, "Shadows of the Past" refers
: You can optionally talk to Daliat at Lane Ends, who will help you with Belmont if you kill certain traitors for him.