The Colognian dialect, or Kölsch is a variety of the German languages. People in and around the city of Cologne in the West of Germany use Kölsch. Nowadays most of them have High German as their primary language or secondary language.

Usage 
About 250,000 people actively speak Kölsch.
More than 2,500,000 people understand Kölsch well and use some Kölsch, or a variant, somehow.
An estimated 20,000,000 to 30,000,000 people understand it partially.

Pronunciation 
How to say "Kölsch"? Take the beginning from "kernel" or "colonel"; next take a real dark, long "l" as in "bold", or "ball"; then append a "sh" as in "shrimps", or "ti" as in "nation". That's the sound "Kölsch". However, the German "ö" is not exactly the same as an English "o", but a sound between "o" and "e".

Etymology 
The word 'Kölsch' comes from the Name of the City of Cologne.
It is 'Köln' in native tongue, yet 'Kölle' in Kölsch.
Now by ordinary German word building rules, 'kölnisch' means 'belonging to Cologne', 'related to Cologne', 'in Cologne', 'from Cologne'—as in 'kölnisch Wasser' (Eau de Cologne). The word 'kölnisch', or 'köllesch', shortened to 'kölsch' in local tongue, became a shorthand noun for the local beer and the local language, or dialect.

Today's name of the city stems from ancient times of the Roman occupation of Northern Germany 100 years before Christ, and later. In the place of a longer existing German tribal settlement, the Romans built a fort or castle —
then, approximately under the reign of Julius Caesar, enhanced it to a colony (Latin: colonia) with religious and city rights.
Part of its Roman name stuck, 'Colonia Clavdia Ara Agrippinensivm Oppidvm Vbiorum' became 'Köln' over the centuries.

History 
Although Kölsch speakers occasionally claim that it is rooted in pre-Roman times, Kölsch's ripuarian base developed from a mix of Lower German and Middle High German in medieval times. It learned from other languages through political and trade connections during the times of the Hanse, and from various waves of immigration. In modern times, there were:
 Remarkable French influences since Napoleon's occupation of the city (1794-1815)
 Prussian influences as Prussian kings took over from the French army
 Dutch influences by immigration, trade, and neighborhood
 Some English influences through the British and American armies, European integration and worldwide globalization since 1945
 Recently minor influences by migrants from Southern Europe and Turkey start evolving

Special properties 
Kölsch has outstanding or unique properties. Here are some:
 Richness. There is only one language in Europe that has as many different vowels as Kölsch. There are a huge number of different sounds that sound like 'sh', but if someone gets them wrong, he will be understood as a foreigner.
 Tolerance paired with individuality. Kölsch is not so outstanding among the many dialects around it. These are both similar and different. Kölsch integrates new variants and deviations easily and quickly. There is no concept of right or wrong, only of difference. It is all right to be different, as every individual is different somehow all the time.
 Kölsch is unusually well documented. Some linguists of the local universities have shown great interest in Kölsch and the ripuarian dialects, and research on them. Outside the world of science, the Akademie för uns Kölsche Sproch (Academy in favour of our Kölsch language) offers regular courses, classes, excursions for everybody. They publish a dictionary, a grammar, and phrase books. It is probably the only institute of its kind worldwide.

Socio-cultural 
After the Second World War, Cologne took up and integrated a huge number of former inhabitants from the former East German regions, which now are part of Poland.
That has not had a remarkable impact on the Kölsch language; but on the immigrants.
They soon began to integrate into the social life and otherwise, they began to learn Kölsch.
Naturally they initially were not perfect speakers.
The Kölsch language recognized that, and quickly created a word for them: "imi" ('imitating' or 'imitated' Kölsch).
As they lerned Kölsch well over the years, you could hear the word 'imi' less often.
It came back recently, when the wall that separated East and West Germany was taken down.

People who speak Kölsch 
 Jacques Offenbach, (1819–1880), cellist, composer, initiator of the genre 'operetta'
 Konrad Adenauer, (1876-1967), Cologne's mayor for long, later the first German prime minister (chancellor) after the second world war
 Karl Blömer, body builder, awarded "Mister Universum"
 Heinrich Böll, (1917-1985), writer and novelist, president of the German and the international Pen Club, received the nobel prize for literature in the year 1972
 Peter Müller 'Dä Aap', (1927-1992), middle-weight boxing champion
 Peter Ludwig, (1925-1996), industry leader, patron and collector of modern art, founder of six important museums spread over Western Germany
 Willy Millowitsch, (1909-1999), actor, TV-star, entertainer, proprietor of his own theatre in Cologne
 Mario Adorf, (born 1930), actor and writer
 Michael Schumacher, (born in 1969), formula-one car-racing world champion

Kölsch music 
 Willi Ostermann, (1876-1936) was a parodist, poet, composer, singer, songwriter, editor and publisher. He is extremely popular in the Kölsch Region. He created a treasure of Kölsch songs. Many of Ostermann's songs are in everybody's active memory in Cologne and about. People sing them on various occasions and music groups ubiquitously performed them all the time until today.
 Can is a Kölsch rock group that reveived much international acclamation from insiders in the late 1960s, when they started a new style of electronic music. General public became aware of them only about 20 years later. Then other musicians had successfully adopted their style. Most of their music is instrumental. If there is voice in their compositions, it is mostly used similar to any other instrument.
 de Bläck Fööss (the Naked Feet) were the first publicly recognized beat band to sing in Kölsch language. The professional musicians, successful in other projects, just for fun recorded a nice Kölsch song together, in 1969. The record became a little local success, they decided to follow that path and started a huge success. Over the years, they had a series of local top hits, occasionally well received even outside the area where people understand Kölsch. Today they regularly draw audiences of 20,000 or 30,000 people several times a year. Their repertoire covers most styles of modern popular music, and various language variants of Kölsch.
 BAP is a Kölsch rock group. They always have been a tour band and successfully perform throughout Germany.
 de Höhner (the Cocks and Hens) is a group playing popular, rock, beat, dancing, and drinking songs, almost all of them use an easy Kölsch. They have had a top hit in Germany and Number One at the Oktoberfest in Munich. Munich is far away from Cologne; people in Munich have a completely different language, they usually do not comprehend Kölsch.

References

Other websites 

 Moselfränkisches Wörterbuch (Mosel-Frankian Dictionary, in German)
 WiKoelsch  Test Wiki in Ripuarian languages, including Kölsch.

German dialects
Languages of Germany
Cologne