Hello Fran,
Hendrick Mommers was a Dutch painter. He was born in Haarlem and was a so called " Italianisant," which means he (and many other painters from Holland, Germany, France and so on) went to Italy to paint the romantic landscapes and other interesting things.These painters - and especially the Dutch painters - went abroad because they could'nt pay the fee for the so called : "Gilde." The st. Lucas-gilde was expensive for painters, so only the very good and popular ones could pay these fees, the rest of the painters went abroad to avoid these fees. But some of them became popular and their paintings became very expensive only after their death.Many museums all over Europe have paintings from Mommers, and even in Russia are paintings in museums.
He painted many marketscenes and landscapes. I am a painting-restorer myself and I have restored a painting of Mommers a few years ago, a romantic scenery with a castle and mountains and many figures. And I must say: since I restored this painting I have a deep respect for his skills. I think he must have used pencils with one hair. He is so very precise. And how he played with the light !!
I hope you have enough information for now. Please don't hesitate when you have more questions about this great -and yet small- master.
Guido