Multi-region SaaS data sovereignty

Design the multi-region architecture for a B2B HR/payroll SaaS serving enterprise tenants in the US, EU, and India. EU tenant data must never leave the EU and Indian tenant data must stay in India (data-sovereignty law), yet the company wants a single global application and the ability to recover a region within an hour if it's lost. How do you place tenant data, route requests, and do disaster recovery without violating sovereignty?