At the opening on Wednesday morning, the Stockholm Stock Exchange's broad OMXS index surged by around 4 percent.
This follows an agreement between the US and Iran on a two-week ceasefire that also includes the opening of the Strait of Hormuz.
Asian stock markets rose strongly overnight. Tokyo closed more than 5 percent higher. In the US, futures point to gains of around 3 percent.
The price of oil has fallen about $17 to around $93 a barrel for North Sea oil.
As a direct effect of reduced inflation concerns when energy prices fall, coupled with increased risk appetite in financial markets, market interest rates have fallen sharply in Sweden and globally. Swedish bond yields have fallen by between 0.15 and 0.20 percentage points, which should put downward pressure on banks' mortgage lending rates, among other things.
The krona has strengthened considerably. One dollar bought 9.29 kronor this morning and one euro 10.86.
