Fricktal was a canton of the Helvetic Republic from February 1802 to February 1803, consisting of that part of the Breisgau (in Habsburg Further Austria) south of the Rhine ("the Fricktal"). Now, the territories of Fricktal form the districts of Rheinfelden and Laufenburg in the canton of Aargau.
In 1799, a year after the proclamation of the Helvetic Republic, French Revolutionary troops marched into the Fricktal. Thanks to good relations with leading French and Swiss politicians, the brothers Karl and Sebastian Fahrländer from Ettenheim and some colleagues were able to proclaim the creation of an independent canton of Fricktal, relying on the treaties of Campo Formio (1797) and Lunéville (1801) for the legal basis of this proclamation.
A constitution was written in the rectory of Eiken in December 1801; on 20 February 1802 the new canton was finally declared, with Laufenburg as its capital. This impetuous action of the governor Sebastian Fahrländer met with some criticism, however; his opponents met with community representatives in a guesthouse in Frick in September 1802 — the governor was unseated and the capital was relocated to Rheinfelden.
The Fricktal ("Frick Valley") region is the northwest extension of the Swiss canton of Aargau. It is situated in Northwestern Switzerland east of Basel, between the High Rhine forming the border with Germany in the north and the Jura Mountains in the south. The Fricktal contains the districts of Laufenburg and Rheinfelden. The region takes its name from its former chief village Frick.
In the Early Middle Ages, Fricktal formed part of the Alamannian Augstgau shire between the Rhine and Aar rivers, from the 10th century onwards of the smaller Frickgau region within Upper Burgundy. The western Fricktal was held by the Burgundian Lords of Rheinfelden, their last scion Rudolf of Rheinfelden became Duke of Swabia in 1057 and upon his death in 1080 his possessions passed to his son in law Berthold II from the House of Zähringen. After the extinction of the line in 1218, the area eventually passed to the Counts of Habsburg, who already held the Vogtei of Laufenburg.
After the Habsburg dynasty had lost large parts of its original Swabian possessions south of the Rhine to the Swiss Confederacy at the 1386 Battle of Sempach, the remaining Fricktal was administered from the Oberamt Breisgau of Further Austria (Vorderösterreich) at Freiburg, while the adjacent Unteraargau region to the south was finally conquered by the Swiss at Bern in 1415. In 1469 the indebted Archduke Sigismund of Further Austria sold the Breisgau with Fricktal to the Burgundian Duke Charles the Bold, nevertheless upon Charles' death in 1477 it reverted to Archduke Maximilian I of Habsburg by marriage with the duke's daughter Mary the Rich.