To delete an AWS IAM Role, Policies need to be detached first: this script automates the tedious necessary steps.

delete-iam-role

#!/usr/bin/env bash
#

set -eu

ROLE=${1:-}
if [[ -z ${ROLE} ]]; then
  printf "Usage: delete-iam-role ROLE\n\nERROR: ROLE must be specified\n"
  exit 1
fi

POLICIES=$(aws iam list-attached-role-policies \
    --role-name ${ROLE} | \
  jq -r ".AttachedPolicies[].PolicyArn")

for policy in ${POLICIES}; do
  aws iam detach-role-policy \
    --role-name ${ROLE} \
    --policy-arn ${policy}
done

aws iam delete-role --role-name ${ROLE}
echo "SUCCESS: Done, ${ROLE} deleted"