Asterix lives around 50 BC in a fictional village in northwest Gaul (Armorica), the only part of that country not yet conquered by Julius Caesar. The inhabitants of the village gain superhuman strength from drinking a magic potion prepared by the druid Getafix (originally Panoramix - names of all characters except "Asterix" and "Obelix" vary from one translation to another). Many books in the Asterix series have as their main plot the attempt by the Roman army of occupation to prevent the druid from making the potion, or the attempt to get some of it for their own use. Such attempts are inevitably foiled by Asterix and his friend Obelix.
The humour encountered in the Asterix comics often centres on anachronistic caricatures and tongue-in-cheek stereotypes of contemporary European nations and French regions. In Asterix and the Goths, for instance, the Goths are represented as militaristic and regimented, reminiscent of late nineteenth and early twentieth century Germans. The helmets worn by these Goths even resemble the German pickelhaube helmets worn up to World War I and one of their leaders bears an uncanny resemblance to Otto von Bismarck. The British are shown as polite, drinking warm beer or hot water (before the first tea has been brought to England by Asterix) and boiling all their food. Spain is the cheap country down south where people from the North vacation (and demand to eat the same food as they are used to at home). Some caricatures of the traits of certain French regions are also used (the people from Normandy cannot give a straight answer; the people from Marseille play boules and exaggerate matters...). Some of the side characters are caricatures of existing French people of the same era, particularly from television and the spectacles; in Obelix and Co., the young Roman bureaucrat is a caricature of young Jacques Chirac.
In spite of this stereotyping and the streaks of French chauvinism, it has been very well received by cultures around the world.
The stories also feature allusions to major artistic works (such as Pieter Bruegel's Peasant Wedding and Victor Hugo's story of the battle of Waterloo from Les Châtiments in Asterix in Belgium), historical personalities (Napoleon, Louis XIV of France), famous places (Le Moulin Rouge).... 
However, in many other respects the series reflects life in the 1st century BC as accurately as can be expected from the medium. For example, the multistoried apartments in Rome- the insulae- has Obelix remarking that one man's roof is another man's floor and consequently "These Romans are crazy"- his favourite line.The text makes relatively regular use of original Latin proverbs, and allusions to Julius Caesar's De Bello Gallico, a book about the conquest of Gaul, later used as an introductory text to Latin. Some jokes are made about Caesar's use of the third person to write about himself.
A key feature of the text of the Asterix books are the constant puns used as names of characters; The names of the two protagonists come from the French names for the asterisk and the obelisk. English language examples include the chief (Vitalstatistix), the druid (Getafix), the woeful bard of the village (Cacofonix), the fishmonger (Unhygienix), an old man (Geriatrix) with a young wife. Incidental characters often feature names like "Hiphiphurrax" and "Mykingdomforanos". This punning tradition occurs in other languages; for example, in the French original, the chief is called "Abraracourcix", derived from the phrase "a bras raccourcis" meaning 'with arms raised and ready, ready to punch'. The Egyptian in Astérix Légionnaire is named "Courdeténis" in French, "Ptenisnet" in English.