There is wide spread issue in at AWS affecting IAM.

UPDATE:

[RESOLVED] Increased API Error Rates Between June 11 9:56 PM PDT and June 12 6:40 AM PDT, AWS IAM experienced increased error rates and latencies on the AWS IAM CreateRole and CreateServiceLinkedRoles APIs. The issue has been resolved and the service is operating normally.

From https://status.aws.amazon.com/:

Increased IAM API Error Rates

We have identified the root cause of the increased error rates and latencies on the AWS IAM CreateRole and CreateServiceLinkedRole APIs and are working towards resolution. Other AWS services such as AWS CloudFormation whose features require these actions may also be impacted. User authentications and authorizations are not impacted.

11:30 PM PDT We are investigating increased error rates and latencies on AWS IAM administrative APIs with potential impact in multiple regions. IAM role creation is impacted. Other AWS services whose features require these actions may also be impacted. User authentications and authorizations are not impacted.

Jun 12, 12:03 AM PDT We continue to investigate increased error rates and latencies on AWS IAM administrative APIs with potential impact in multiple regions. IAM role creation is impacted. Other AWS services like AWS CloudFormation whose features require these actions may also be impacted. User authentications and authorizations are not impacted.

Jun 12, 2:12 AM PDT We have identified the root cause of the increased error rates and latencies on the AWS IAM CreateRole and CreateServiceLinkedRole APIs and are working towards resolution. Other AWS services such as AWS CloudFormation whose features require these actions may also be impacted. User authentications and authorizations are not impacted.

Jun 12, 3:30 AM PDT We wanted to provide you with more details on the issue causing increased error rates and latencies on the AWS IAM CreateRole and CreateServiceLinkedRole APIs. While we have identified the root cause and are working towards resolution, with an issue like this, it is always difficult to provide an accurate ETA, but we expect to restore access to the CreateRole and CreateServiceLinkedRole APIs within the next several hours. We are working through the recovery process now and will continue to keep you updated if this ETA changes. IAM user authentications and authorizations are not impacted. Other AWS services like AWS CloudFormation whose features require these actions may also be impacted.

I just got this error today. I have very few roles so was surprised. After reading this post I simply clicked the 'create role' button a few times and on the 4th attempt the role was created.

This happened to me today. I clicked again on Create Role and it seems to have already worked even after producing a rate exceeded message:

Entity already exists This entity already exists. Role with name rekognition-lambda-role already exists.