the british isles were invaded by germanic tribes in the 5th century which pushed the celtic speakers north and west to Scotland Wales and Ireland, the germanic tribes (Angles Saxons and Jutes) spoke their own languages which then morphed into Old English(a completely different language to the modern english) this was spoken right up until the 10th century then middle english from then til around 1500ad it then slowly developed to modern english and what we know recognise today.
So we all spoke a celtic form of language til we got invaded, language changes and modifies all the time, but that isn't a reason to let a whole language die.
Any language should be celebrated and retained. Northern Ireland has suffered in recent times by language being used as a weapon, which is unfortunate as those normally wielding it don't have a very good grasp of it.
Despite this I fail to see how a language in it's entirity can be viewed as 'disgusting' all languages have words for disgusting things.
I wish I was bi-lingual.