Of all these languages Irish is the best preserved, and it is possible to follow its written literature back into the past for some thirteen hundred years; while much of the most interesting matter has come down to us from pagan times. It has left behind it the longest, the most luminous, and the most consecutive literary track of any of the vernacular languages of Europe, except Greek alone. For centuries the Irish and their language were regarded by the English as something strange and foreign to Europe. It was not recognized that they had any relationship with the Greeks or Romans, the French, the Germans, or the English. The once well-known statesman, Lord Lyndhurst, in the British parliament denounced the Irish as aliens in religion, in blood, and in language. Bopp, in his great Comparative Grammar, refused them recognition as Indo-Europeans, and Pott in 1856 also denied their European connection. It was left for the great Bavarian scholar, John Caspar Zeuss, to prove to the world in his epoch-making "Grammatica Celtica" (published in Latin in 1853) that the Celts were really Indo-Europeans, and that their language was of the highest possible value and interest. From that day to the present it is safe to say that the value set upon the Irish language and literature has been steadily growing amongst the scholars of the world, and that in the domain of philology Old Irish now ranks close to Sanscrit for its truly marvellous and complicated scheme of word-forms and inflections, and its whole verbal system. The exact place which the Celtic languages (of which Irish is philologically far the most important) hold in the Indo-European group has often been discussed. It is now generally agreed upon that, although both the Celtic and Teutonic languages may claim a certain kinship with each other as being both of them Indo-European, still the Celtic is much more nearly related to the Greek and the Latin groups, especially to the Latin.