The first thing that you need to know about Barcelona is that it is in the region of Cataluña. You may already know this simple geographical titbit, but it can hold some fruitful information for travellers eating vegetarian and vegan in Barcelona.
Firstly, Catalans are fiercely proud of their distinct language (an official EU minority language) and culture- not to mention their fiestas and food. Cataluña´s regional government is even on a widely debated mission to become independent from the rest of Spain. Irrespective of whether the people of Cataluña feel that this is the right political road to take, they are very proud of their distinct heritage and Catalan culture.
This might seem irrelevant, but what this means for vegetarians and vegans is that you may be received more favourably speaking a little Catalan, as well as English or Spanish. Many people in Barcelona speak all three and it can depend on the person as to which they prefer. In any case, a great phrase to know is ´I am vegetarian´: sóc vegetarià.
Secondly, Barcelona is famous for its seafood, as the city is on the coast, and many Catalans do not understand the concept of vegetarianism or veganism: a ´vegetable´ salad or dish may actually also contain fish, like tuna. This might be something to look out for and you can ask for a dish ´without meat or fish´ in English, or in Catalan as well, if you like: ´sense carn o peix´.
Nonetheless, a feisty, eclectic vegetarian food culture in Barcelona is on the rise. There are many fantastic places to eat vegan or vegetarian in the city, whether you would like to try traditional Catalan tapas, the Catalan version of Paella (that has noodles instead of rice), gazpacho (a vegetarian Catalan tomato soup), organically grown natural foods or international dishes.