A good question–and the answer is not Eleanor Roosevelt:
In fact, as Waltz shows, Roosevelt supplied neither the text nor the substantive ideas that shaped the UDHR. Ricardo Alfaro, former President of Panama, proposed the idea and first draft of such a Declaration, which was taken up by many others including public intellectuals such as HG Wells. While early drafts were worked on by Rene Cassin of France, along with many US lawyers, each clause was voted on by member states, and many suggestions came from drafters from small and newly de-colonised states. The Latin American states promoted social and economic rights, while the Soviet Union concentrated on racial discrimination – a convenient way of bashing the US, as well as colonial states.
The desire for emancipation of all, emphasising that rights applied to everyone everywhere, emerged as a major concern. Significant additions were made by newly de-colonised states regarding, slavery, discrimination, the rights of women and the right to national self determination.