See J. Katz, Tradition and Crisis (1961).
In a more restricted sense, haskalah can also denote the study of Biblical Hebrew and of the poetical, scientific, and critical parts of Hebrew literature. The term is sometimes used to describe modern critical study of Jewish religious books, such as the Mishnah and Talmud, when used to differentiate these modern modes of study from the methods used by Orthodox Jews.
The example of Moses Mendelssohn (1729–86), a Prussian Jew, served to lead this movement, which was also shaped by Aaron Halle-Wolfssohn (1754–1835) and Joseph Perl (1773–1839). Mendelssohn's extraordinary success as a popular philosopher and man of letters revealed hitherto unsuspected possibilities of integration and acceptance of Jews among non-Jews. Mendelssohn also provided methods for Jews to enter the general society of Germany. A good knowledge of the German language was necessary to secure entrance into cultured German circles, and an excellent means of acquiring it was provided by Mendelssohn in his German translation of the Torah. This work became a bridge over which ambitious young Jews could pass to the great world of secular knowledge. The Biur, or grammatical commentary, prepared under Mendelssohn's supervision, was designed to counteract the influence of traditional rabbinical methods of exegesis. Together with the translation, it became, as it were, the primer of Haskalah. Haskalah did not stay restricted to Germany, however, and the movement quickly spread throughout Europe (Map of the spread of Haskalah). Adherents of the haskalah movement were called maskilim (משכילים).
Language played a key role in the haskalah movement, as Mendelssohn and others called for a revival in Hebrew and a reduction in the use of Yiddish. The result was an outpouring of new, secular literature, as well as critical studies of religious texts. Julius Fürst along with other German-Jewish scholars compiled Hebrew and Aramaic dictionaries and grammars. Jews also began to study and communicate in the languages of the countries in which they settled, providing another gateway for integration.
Yiddish theatre played a key role in Lodz, Poland which was known as the "second city of the Haskalah" and was performed in the Rosenfeld textile factories. Rosenfeld was a division of Rosenfeld of Berdychiv (Berdicheff) which was called "the Jerusalem of the Volhynia" by a chief maskil, the merchant prince Rosenfeld who traced himself from the exilarchs of Bagdad through a Rosh-ha-golah (hence:Rosenfeld) who had been sent to Kaifeng, China in 1163 when China was Islamised, to marry a princess of the old Wei kingdom and establish a synagogue there. About 1840 Rosenfeld of Berdychiv acquired the Astor House Hotel (now the Pujiang Fandian) across the street from the Russian Embassy in Shanghai and Jewish merchants in Kaifeng exported cotton to Berdychiv. There is a photograph http://en.wikipedia.org/wiki/Image:Jacob_Rosenfeld.jpg of Jacob Rosenfeld standing between Chen Yi and Liu Shaoqi who died a political prisoner in Kaifeng. Rosenfeld removed to Russian Hill in San Francisco in 1900 where his daughter married Albert Less, a member of the Levi-Strauss family. As the line now traces itself through a female, it is generally acknowledged that the authority of the exilarchs and maskilim has now passed to Yosef Dayan, current claimant to the Israeli throne.
(NB: This Jacob Rosenfeld was a medical doctor from the Austrian branch of the Rosenfeld family. He became China's General Luo and there is a hospital in China today that is named after him.)
These Davidic dynasties concerned with the Haskalah have recently been put on a firm genetic genealogical basis: see http://www.davidicdynasty.org/ and go to dna/php for the Davidic DNA test pool http://www.familytreedna.com/surname_join.asp?code=E43088&special=true for the Davidic Dynasty DNA database the specific Davidic Dynasty DNA tests: Men-Y-DNA25+mtDNA Women-mtDNA.
One facet of haskalah was a widespread cultural adaptation, as those Jews who participated in the enlightenment began in varying degrees to participate in the cultural practices of the surrounding Gentile population. Connected with this was the birth of the Reform movement, whose founders such as Israel Jacobson and Leopold Zunz rejected the continuing observance of those aspects of Jewish law which they classified as ritual, as opposed to moral or ethical. Even within orthodoxy the Haskalah was felt through the appearance of the Mussar Movement in Lithuania and Torah im Derech Eretz in Germany. Enlightened Jews sided with Gentile governments in plans to increase secular education amongst the Jewish masses, bringing them into acute conflict with the orthodox who believed this threatened Jewish life.