You should just try washing it. It's possible it's just filthy. Fill a mixing or the sink with detergent and some Oxiclean and let it soak for a while.

I have used Chlorox to whiten ecru lace curtains. You must use very little because it will make holes if you use too much. I don't think Oxyclean will hurt it but might not work for ecru. It doesn't take the color out of my khaki pants.

Thank you for your responses. I see so much of that ECRU color in vintage crochet tablecloths, and I personally do not like it at all, but I admire the work and time someone put into making it. I was hoping that there was a white dye on the market, or a way to get that color out, making it white without damaging the tablecloth.

BNice... unfortunately there is no such thing as a white "dye". There are white pigments but they are more like paint pigments than dyes and can yield a stiff product.

The end result will totally depend on how the fabric was dyed originally. If it was tea died or similarly dyed using a natural substance, an overnight OxyClean soak will likely turn it "white". Now it's only going to turn it as white as natural cotton.

If you want it to be the dazzling, unnatural white of today's whites, you're going to have to oxy bleach, chlorine bleach and then bluing it. The "white" everyone thinks of as white today is actually slightly blue.

- IT Geek

did the chlorox bleach whiten the ecru cloth

I would try Rit Color Remover.