diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0251f2d9d..11178c449 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
-project(xgboost LANGUAGES CXX C VERSION 1.6.0)
+project(xgboost LANGUAGES CXX C VERSION 2.0.0)
 include(cmake/Utils.cmake)
 list(APPEND CMAKE_MODULE_PATH "${xgboost_SOURCE_DIR}/cmake/modules")
 cmake_policy(SET CMP0022 NEW)
diff --git a/R-package/DESCRIPTION b/R-package/DESCRIPTION
index 4c9a0db1f..736dea05e 100644
--- a/R-package/DESCRIPTION
+++ b/R-package/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: xgboost
 Type: Package
 Title: Extreme Gradient Boosting
-Version: 1.6.0.1
+Version: 2.0.0.1
 Date: 2022-03-29
 Authors@R: c(
   person("Tianqi", "Chen", role = c("aut"),
diff --git a/doc/model.schema b/doc/model.schema
index d20d9abb2..b192cabc6 100644
--- a/doc/model.schema
+++ b/doc/model.schema
@@ -247,7 +247,7 @@
       "items": [
         {
           "type": "number",
-          "const": 1
+          "minimum": 1
         },
         {
           "type": "number",
diff --git a/include/xgboost/version_config.h b/include/xgboost/version_config.h
index 10aa39424..3eb87e664 100644
--- a/include/xgboost/version_config.h
+++ b/include/xgboost/version_config.h
@@ -4,8 +4,8 @@
 #ifndef XGBOOST_VERSION_CONFIG_H_
 #define XGBOOST_VERSION_CONFIG_H_
 
-#define XGBOOST_VER_MAJOR 1
-#define XGBOOST_VER_MINOR 6
+#define XGBOOST_VER_MAJOR 2
+#define XGBOOST_VER_MINOR 0
 #define XGBOOST_VER_PATCH 0
 
 #endif  // XGBOOST_VERSION_CONFIG_H_
diff --git a/jvm-packages/pom.xml b/jvm-packages/pom.xml
index cd5fedf7d..ef79b2ef8 100644
--- a/jvm-packages/pom.xml
+++ b/jvm-packages/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>ml.dmlc</groupId>
     <artifactId>xgboost-jvm_2.12</artifactId>
-    <version>1.6.0-SNAPSHOT</version>
+    <version>2.0.0-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>XGBoost JVM Package</name>
     <description>JVM Package for XGBoost</description>
diff --git a/jvm-packages/xgboost4j-example/pom.xml b/jvm-packages/xgboost4j-example/pom.xml
index da6ef2be6..10c6010d2 100644
--- a/jvm-packages/xgboost4j-example/pom.xml
+++ b/jvm-packages/xgboost4j-example/pom.xml
@@ -6,10 +6,10 @@
     <parent>
         <groupId>ml.dmlc</groupId>
         <artifactId>xgboost-jvm_2.12</artifactId>
-        <version>1.6.0-SNAPSHOT</version>
+        <version>2.0.0-SNAPSHOT</version>
     </parent>
     <artifactId>xgboost4j-example_2.12</artifactId>
-    <version>1.6.0-SNAPSHOT</version>
+    <version>2.0.0-SNAPSHOT</version>
     <packaging>jar</packaging>
     <build>
         <plugins>
@@ -26,7 +26,7 @@
         <dependency>
             <groupId>ml.dmlc</groupId>
             <artifactId>xgboost4j-spark_${scala.binary.version}</artifactId>
-            <version>1.6.0-SNAPSHOT</version>
+            <version>2.0.0-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.apache.spark</groupId>
@@ -37,7 +37,7 @@
         <dependency>
             <groupId>ml.dmlc</groupId>
             <artifactId>xgboost4j-flink_${scala.binary.version}</artifactId>
-            <version>1.6.0-SNAPSHOT</version>
+            <version>2.0.0-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
diff --git a/jvm-packages/xgboost4j-flink/pom.xml b/jvm-packages/xgboost4j-flink/pom.xml
index f9bd4aa2a..c5b1da54a 100644
--- a/jvm-packages/xgboost4j-flink/pom.xml
+++ b/jvm-packages/xgboost4j-flink/pom.xml
@@ -6,10 +6,10 @@
     <parent>
         <groupId>ml.dmlc</groupId>
         <artifactId>xgboost-jvm_2.12</artifactId>
-        <version>1.6.0-SNAPSHOT</version>
+        <version>2.0.0-SNAPSHOT</version>
     </parent>
     <artifactId>xgboost4j-flink_2.12</artifactId>
-    <version>1.6.0-SNAPSHOT</version>
+    <version>2.0.0-SNAPSHOT</version>
     <build>
         <plugins>
             <plugin>
@@ -26,7 +26,7 @@
         <dependency>
             <groupId>ml.dmlc</groupId>
             <artifactId>xgboost4j_${scala.binary.version}</artifactId>
-            <version>1.6.0-SNAPSHOT</version>
+            <version>2.0.0-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
diff --git a/jvm-packages/xgboost4j-gpu/pom.xml b/jvm-packages/xgboost4j-gpu/pom.xml
index 2a2abaee8..540038194 100644
--- a/jvm-packages/xgboost4j-gpu/pom.xml
+++ b/jvm-packages/xgboost4j-gpu/pom.xml
@@ -6,10 +6,10 @@
     <parent>
         <groupId>ml.dmlc</groupId>
         <artifactId>xgboost-jvm_2.12</artifactId>
-        <version>1.6.0-SNAPSHOT</version>
+        <version>2.0.0-SNAPSHOT</version>
     </parent>
     <artifactId>xgboost4j-gpu_2.12</artifactId>
-    <version>1.6.0-SNAPSHOT</version>
+    <version>2.0.0-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <dependencies>
diff --git a/jvm-packages/xgboost4j-spark-gpu/pom.xml b/jvm-packages/xgboost4j-spark-gpu/pom.xml
index daa5907c6..b1932f3cc 100644
--- a/jvm-packages/xgboost4j-spark-gpu/pom.xml
+++ b/jvm-packages/xgboost4j-spark-gpu/pom.xml
@@ -6,7 +6,7 @@
     <parent>
         <groupId>ml.dmlc</groupId>
         <artifactId>xgboost-jvm_2.12</artifactId>
-        <version>1.6.0-SNAPSHOT</version>
+        <version>2.0.0-SNAPSHOT</version>
     </parent>
     <artifactId>xgboost4j-spark-gpu_2.12</artifactId>
     <build>
@@ -24,7 +24,7 @@
         <dependency>
             <groupId>ml.dmlc</groupId>
             <artifactId>xgboost4j-gpu_${scala.binary.version}</artifactId>
-            <version>1.6.0-SNAPSHOT</version>
+            <version>2.0.0-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.apache.spark</groupId>
diff --git a/jvm-packages/xgboost4j-spark/pom.xml b/jvm-packages/xgboost4j-spark/pom.xml
index 3fe38f875..3a84233d1 100644
--- a/jvm-packages/xgboost4j-spark/pom.xml
+++ b/jvm-packages/xgboost4j-spark/pom.xml
@@ -6,7 +6,7 @@
     <parent>
         <groupId>ml.dmlc</groupId>
         <artifactId>xgboost-jvm_2.12</artifactId>
-        <version>1.6.0-SNAPSHOT</version>
+        <version>2.0.0-SNAPSHOT</version>
     </parent>
     <artifactId>xgboost4j-spark_2.12</artifactId>
     <build>
@@ -24,7 +24,7 @@
         <dependency>
             <groupId>ml.dmlc</groupId>
             <artifactId>xgboost4j_${scala.binary.version}</artifactId>
-            <version>1.6.0-SNAPSHOT</version>
+            <version>2.0.0-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.apache.spark</groupId>
diff --git a/jvm-packages/xgboost4j/pom.xml b/jvm-packages/xgboost4j/pom.xml
index d60a83b29..10d323c8f 100644
--- a/jvm-packages/xgboost4j/pom.xml
+++ b/jvm-packages/xgboost4j/pom.xml
@@ -6,10 +6,10 @@
     <parent>
         <groupId>ml.dmlc</groupId>
         <artifactId>xgboost-jvm_2.12</artifactId>
-        <version>1.6.0-SNAPSHOT</version>
+        <version>2.0.0-SNAPSHOT</version>
     </parent>
     <artifactId>xgboost4j_2.12</artifactId>
-    <version>1.6.0-SNAPSHOT</version>
+    <version>2.0.0-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <dependencies>
diff --git a/python-package/xgboost/VERSION b/python-package/xgboost/VERSION
index bcfbf475d..d72f26267 100644
--- a/python-package/xgboost/VERSION
+++ b/python-package/xgboost/VERSION
@@ -1 +1 @@
-1.6.0-dev
+2.0.0-dev
diff --git a/src/data/data.cc b/src/data/data.cc
index ff5b2c803..86f73523a 100644
--- a/src/data/data.cc
+++ b/src/data/data.cc
@@ -265,9 +265,11 @@ void MetaInfo::LoadBinary(dmlc::Stream *fi) {
       << " is no longer supported. "
       << "Please process and save your data in current version: "
       << Version::String(Version::Self()) << " again.";
-  CHECK_EQ(major, 1) << msg.str();
-  auto minor = std::get<1>(version);
-  CHECK_GE(minor, 6) << msg.str();
+  CHECK_GE(major, 1) << msg.str();
+  if (major == 1) {
+    auto minor = std::get<1>(version);
+    CHECK_GE(minor, 6) << msg.str();
+  }
 
   const uint64_t expected_num_field = kNumField;
   uint64_t num_field { 0 };