Background: Literary Catalan allows the use of words from different dialects, except those of very restricted use. However, from the 19th century onwards, there is a tendency of favoring words of Northern dialects in detriment of others, even though nowadays there is a greater freedom of choice.
Question: When did the preference of use of words from northern dialects begin?
Answer:<extra_id_0>.
<extra_id_0> 19th century<extra_id_1>