With __self-sovereign identity (SSI)__ the individual identity holders can fully create and control their credentials, without being forced to request permission of an intermediary or centralised authority and gives control over how their personal data is shared and used - wikipedia 
Relationship between entities, identities and attributes / identifiers
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Decentralized identifiers (DIDs) can be used to enable self-sovereign identities
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The user has a means of generating and controlling unique identifier as well as some facility to store identity data.
A SSI can be a decentralised identity, but could also be data from a Social_login, a history of transactions on an e-commerce site, or attestation from friends or colleagues.
In the centralised identity paradigm a person’s identity is provided by some outside entity. In the decentralised identity paradigm the user is at the centre of the framework and there is no need for third parties to issue and administer an identity.
# European Union SSI
The European Union is creating an eIDAS compatible European Self-Sovereign Identity Framework (ESSIF). The ESSIF makes use of decentralized identifiers (DIDs) and the European Blockchain Services Infrastructure (EBSI) - wikipedia
HTML5 webm https://upload.wikimedia.org/wikipedia/commons/7/7a/Meet_the_European_Blockchain_Services_Infrastructure_EBSI.webm
A SSI example in the European Union - wikimedia.org
# See also