From Wikipedia because I'm to busy eating my semla ..
"A semla, vastlakukkel, laskiaispulla or fastlagsbulle/fastelavnsbolle is a traditional sweet roll made in various forms in Sweden,[1] Finland, Estonia, Norway, Denmark, the Faroe Islands and Iceland, associated with Lent and especially Shrove Tuesday in most countries, Shrove Monday in Denmark, parts of southern Sweden, Iceland and Faroe Islands or Sunday of Fastelavn in Norway. In Sweden it is most commonly known as just semla (plural: semlor), but is also known as fettisdagsbulle (lit. "fat tuesday roll"). In the southern parts of Sweden, as well as in Swedish-speaking Finland, it is known as fastlagsbulle (plural: fastlagsbullar; semla on the other hand means a plain wheat bun with butter, called "fralla" in Sweden). In Estonia it is called vastlakukkel. In Norway and Denmark it is called fastelavnsbolle. In Iceland, it's known as a bolla and served on Bolludagur. .. "
"A semla, vastlakukkel, laskiaispulla or fastlagsbulle/fastelavnsbolle is a traditional sweet roll made in various forms in Sweden,[1] Finland, Estonia, Norway, Denmark, the Faroe Islands and Iceland, associated with Lent and especially Shrove Tuesday in most countries, Shrove Monday in Denmark, parts of southern Sweden, Iceland and Faroe Islands or Sunday of Fastelavn in Norway. In Sweden it is most commonly known as just semla (plural: semlor), but is also known as fettisdagsbulle (lit. "fat tuesday roll"). In the southern parts of Sweden, as well as in Swedish-speaking Finland, it is known as fastlagsbulle (plural: fastlagsbullar; semla on the other hand means a plain wheat bun with butter, called "fralla" in Sweden). In Estonia it is called vastlakukkel. In Norway and Denmark it is called fastelavnsbolle. In Iceland, it's known as a bolla and served on Bolludagur. .. "