Wiki4R will create an innovative virtual research environment (VRE) for Open Science at scale, engaging both professional researchers and citizen data scientists in new and potentially transformative forms of collaboration. It is based on the realizations that (1) the structured parts of the Web itself can be regarded as a VRE, (2) such environments depend on communities, (3) closed environments are limited in their capacity to nurture thriving communities. Wiki4R will therefore integrate Wikidata, the multilingual semantic backbone behind Wikipedia, into existing research processes to enable transdisciplinary research and reduce fragmentation of research in and outside Europe. By establishing a central shared information node, research data can be linked and annotated into knowledge. Despite occasional uses of Wikipedia or Wikidata in research, significant barriers to broader adoption in the sciences or digital humanities exist, including lack of integration into existing research processes and inadequate handling of provenances. The proposed actions include providing best practices and tools for semantic mapping, adoption of citation and author identifiers, interoperability layers for integration with existing research environments, and the development of policies for information quality and interchange. The effectiveness of the actions will be tested in pilot use cases. Unforeseen barriers will be investigated and documented. We will promote the adoption of Wiki4R by making it easy to use and integrate, demonstrate the applicability in selected research domains, and provide diverse training opportunities. Wiki4R leverages the expertise gained in Europe through the Wikidata and DBpedia projects to further strengthen the established virtual community of 14000 people. As a result of increased interaction between professional science and citizens, it will provide an improved basis for Responsible Research and Innovation and Open Science in the European Research Area.