LONDON — In the days since Saudi Arabia inflamed tensions with Iran by executing 47 people, including a Shiite cleric, European observers have been quick to condemn the action, reflecting broader concern across the Continent about Saudi policy and its role in the tumult rolling through the Middle East.

Opposition in Europe to the death penalty — and harsh corporal punishment, including the flogging of a Saudi blogger who has become something of a cause célèbre in Europe — is just one element of the criticism of the Saudi monarchy. Even as European governments continue to view Saudi Arabia as a vital if problematic stabilizing force in the region, as well as a rich market for European arms and other products, European opinion has grown increasingly critical of Saudi support and financing for Wahhabist and Salafist preachers who have contributed to the Sunni extremist ideology that has fueled Al Qaeda and the Islamic State.

In addition, the European Union and six major world powers reached a deal in Vienna over the summer to contain Iran’s nuclear program, and Iran is seen as essential to ending the five-year-old civil war in Syria, which has fueled a surge of migrants to the Continent, the highest number since World War II.

So for many Europeans, Iran — long a pariah because of its anti-Western rhetoric and its nuclear program — has suddenly become, at least in comparison with Saudi Arabia, an object of sympathy.