The first season takes place from 1912 until 1914, when World War I breaks out. The second season spans the war, and concludes in 1918 with the outbreak of the Spanish Flu. Did your designs change from one season to the next?

They did change because of the passage of time and the huge impact of the war. Fashion virtually came to a standstill. The skirts before the war for the fashionable women were quite restricting. All the clothes started to relax a bit. A lot of women had to help in war work, and Julian [Fellowes] emphasized that in the script. I think there was less focus on expensive fabrics and more on the silhouette. The shape changes slightly. It’s subtle. In the evening they’re still wearing their grand evening dresses because they would have lasted. They would have two or three and repeat in real life. It would have been very bad taste to be dressed up during the day. Colors were more somber. I had to try and reflect all that.

The costumes worn by the servants look much simpler than those worn by the aristocrats. Do the servants’ clothes present any challenges of their own?

I think the challenge is it needs to reflect the period and the status of each person. It couldn’t reflect the fashion of the masses. You have to select them in their time. But at the same time make each character look good in her uniform. For the women, each costume is made for them. You can do a lot of adjusting for a maid that you can’t do for a person upstairs. To make her neck more beautiful you can cut the neck of her dress slightly lower. There are lots of things you can do to make it look as good as possible.

What about the clothes for the Crawley family?

I think the difficulty for the upper classes was finding the weight of fabric that they would have used in those days, and the lusciousness and embroidery and beadings. Often my problem was that an evening dress — for Elizabeth McGovern, it was one that was heavily beaded with a silk panel that was original the dress — would deteriorate. We then had to take the panel and make another dress around it. That’s the problem of using vintage pieces.