The Silverbloods on the other hand will TAKE what they want, even if that means killing you or framing you and using you as slave labor and extorting an entire city through fear tactics by using a created "Boogeyman" (i.e. the Foreswarn) that would have, in all likelyhood, never have actually entered the city to attack anyone and would have instead just made the entire region so inhospital to travelers that Markarth would have starved. Look what they did at Karthwasten and during the Foreswarn Conspiracy.
To your point (I'm helping ),
4E 174 — The Reachmen rebel, taking over the Reach.
- With the Empire busy fighting the Thalmor, Markarth is left undefended. The Reachmen take the opportunity to overthrow the Nord occupiers, retaking The Reach easily. The changeover is relatively peaceful, with only a few of the harshest Nord landowners being put to death.
4E 176 — Ulfric Stormcloak retakes The Reach, instigating the Markarth Incident.
- The Empire and the son of the deposed Jarl promise Ulfric Stormcloak free worship of Talos in exchange for retaking The Reach. Ulfric forms a Nord militia and crushes the Reachmen at Markarth with the aid of the thu'um. The survivors flee into the wilds, forming a group called the Forsworn. Ulfric is arrested when the Thalmor discover the open worship of Talos. Ulfric and his men are eventually released, but the incident kindles what will become the Stormcloak Rebellion.
We know that the Reachmen were predominantly peaceful when they retook Markarth, and we also know that the Silver-Bloods back Ulfric, who butchered dozens of Reachmen and Nords alike in the Markarth Incident.
In the wake of the aftermath of the Great War, you can imagine the backlog on stately matters the Empire had. Before a peace treaty could be resolved with the Forsworn, a militia led by Ulfric Stormcloak sieged the gates of their capital, Markarth. What happened during that battle was war, but what happened after the battle was over is nothing short of war crimes.
Every official who worked for the Forsworn was put to the sword, even after they had surrendered. Native women were tortured to give up names of Forsworn fighters who had fled the city or were in the hills of the Reach. Anyone who lived in the city, Forsworn and Nord alike, were executed if they had not fought with Ulfric and his men when they breached the gates. "You are with us, or you are against Skyrim" was the message on Ulfric's lips as he ordered the deaths of shopkeepers, farmers, the elderly, and any child old enough to lift a sword that had failed in the call to fight with him.
So when a "grateful" Empire accepted Ulfric's victory and sent soldiers to re-establish the rule of law in the Reach, it was no surprise that he would demand to be allowed to worship Talos freely before the Legion could enter. With chaos running through the streets of Markarth and the reports of deaths rising every day, the Empire had no choice but to grant Ulfric and his men their worship.
http://www.uesp.net/wiki/Skyrim:The_Bear_of_Markarth
Thongvor: "What are you hiding, priest?"
Verulus: "I'm not hiding anything. It's closed for a reason."
Thongvor: "Typical Imperial lies. First you take away Talos, now you're keeping us from seeing our honored dead? You and the Jarl will answer for any desecration of my ancestors' bodies."
Verulus: "That's enough, Thongvor. We're done."
http://www.uesp.net/wiki/Skyrim:The_Taste_of_Death
Thongvor's an underrated villain for Stormcloak-haters if you ask me. He's pretty much a Thu'um-less Ulfric.